Undertale/Deltarune NSFW mods?

[losstie27]

13 hours ago, V1de0gam3r said:

This is so awesome! Maybe you could try undyne next?

 

I started sprites for this and realized, how should I handle armor. If my lore here is that the underground physically cannot have clothes because of a magic spell, then surely armor would count under that too. I don't really want to make an exception if possible, but if I don't then it kind of ruins the Undyne reveal

 

9 hours ago, Buddussy said:

Man you got the style down pat, I love it

Very much appreciate it. Unrelated, but I've been meaning to ask, whose the character in your banner?

[v1ed]

1 hour ago, losstie27 said:

I started sprites for this and realized, how should I handle armor. If my lore here is that the underground physically cannot have clothes because of a magic spell, then surely armor would count under that too. I don't really want to make an exception if possible, but if I don't then it kind of ruins the Undyne reveal

 

Very much appreciate it. Unrelated, but I've been meaning to ask, whose the character in your banner?

Maybe you could color her sprite black to still make it a mystery and ominous, like sans in judgment hall.

[Sunshine Recorder]

2 hours ago, losstie27 said:

I started sprites for this and realized, how should I handle armor. If my lore here is that the underground physically cannot have clothes because of a magic spell, then surely armor would count under that too. I don't really want to make an exception if possible, but if I don't then it kind of ruins the Undyne reveal

 

Very much appreciate it. Unrelated, but I've been meaning to ask, whose the character in your banner?

On the topic of armor, how are you going to tackle RG01 and RG02. Since in Undertale, in order to spare them, you have to get RG02 to take off his armor chest piece by cleaning it (RG01 will get all shaky when that happens since he has a romantic attraction towards RG02) and then get RG01 to confess his feelings to RG02 after RG02 takes off his armor chest piece. 
 

If they’re both naked, the method to spare them wouldn’t make any sense (assuming that the dialog stays the same), and by Undertale’s logic, RG01 should already be shaky and flustered at the start of the battle since RG02 is already naked especially with his dick out.

 

 

[losstie27]

Did a quick Catty and Bratty to kill time. The textbox in game unfortunately crops out her nipples so I'll show the full sprite for fun.

 

 

1 hour ago, V1de0gam3r said:

Maybe you could color her sprite black to still make it a mystery and ominous, like sans in judgment hall.

Oh maybe, maybe! Still, her body in armor is drastically different from the one without in her date. I'd like to keep her as accurate as possible. I'll figure something out... 

 

28 minutes ago, Sunshine Recorder said:

On the topic of armor, how are you going to tackle RG01 and RG02. Since in Undertale, in order to spare them, you have to get RG02 to take off his armor chest piece by cleaning it (RG01 will get all shaky when that happens since he has a romantic attraction towards RG02) and then get RG01 to confess his feelings to RG02 after RG02 takes off his armor chest piece. 
 

If they’re both naked, the method to spare them wouldn’t make any sense (assuming that the dialog stays the same), and by Undertale’s logic, RG01 should already be shaky and flustered at the start of the battle since RG02 is already naked especially with his dick out.

 

 

That uhh... That's a good question. If I DO get rid of armor entirely, I'd have to design faces for them too. I could just not touch armor at all for both them and Undyne, and say that the armor is made of magic or something so it doesn't count. Of course, if I did that, Undyne wouldn't be nude in her normal fight, which some might be disappointed with. I could only give them helmets I guess, but that still feels like a cop out, and wouldn't logically make sense (Though with the Royal Guards, they still wear helmets in Deltarune, so those might just BE their faces). I'm really not sure. I kind of forget about their existence. 

[Buddussy]

5 hours ago, losstie27 said:

Very much appreciate it. Unrelated, but I've been meaning to ask, whose the character in your banner?

Buddy Armstrong from Lisa the Joyful

[Buddussy]

1 hour ago, losstie27 said:

Of course, if I did that, Undyne wouldn't be nude in her normal fight, which some might be disappointed with.

Bikini armor bikini armor

[Sunshine Recorder]

20 minutes ago, losstie27 said:

(Though with the Royal Guards, they still wear helmets in Deltarune, so those might just BE their faces). I'm really not sure. I kind of forget about their existence. 

The reason why the Royal Guards still wear their helmets in Deltarune was so that Undertale players can understand that the royal guards in Deltarune resemble the same ones in Undertale. If their helmets were off in Deltarune, then Undertale players would assume that they were two completely new characters, because in Undertale they were never shown with their helmets off and their overworld sprites contained only gray and black pixels, unlike in Deltarune which showed the color of RG01’s fur and RG02’s scales.
 

Also I forgot to mention, but there’s also a green sprite that shows up when RG01 and RG02 attack you, that resembles an armor chestplate (This sprite pops up after you picked the option to clean RG02’s armor), and you have to hit that sprite with your soul, I think 5 times in order to get RG02 to take off his armor chestplate, so that has to be changed, if you want the nude mod to make sense, because if they’re naked, there’s no reason that the sprite should look like a piece of armor.

 

Another thing, at the beginning of Asgore’s fight, Asgore pulls his red trident out from under his cape, how are you going to be able to tackle that in the nude mod, are you going to make Asgore carry the trident the entire time from the throne room to the barrier, or maybe summon his trident at the beginning of the fight either through telekinesis or by just making it appear out of thin air.

[losstie27]

26 minutes ago, Buddussy said:

Bikini armor bikini armor

I could do that, but at that point it just feels like making her sexy for the sake of making her sexy? If that makes any sense. Like, I kind of want there to be a logic to it you know? If I want everyone to be nude, I want a reason. Every character is nude because the barrier destroys clothes? Sure yeah that makes sense, but now I also have to make sure I get rid of things like hats or bows, because those would still be clothes right? Burgerpants, a character whose whole backstory is based around having pants pockets doesn't make much sense now if you think about it, because nobody wears pants (I opted to rename him Burgerbutt because he accidentally sat on Catty and Bratty's food, but I'm not set on that). Bikini armor would logically be super impractical for any reason other than to look sexy, and given that wouldn't be Undyne's (or the Royal Guards in case you wanted them in a bikini too, I don't judge) goal, I don't feel right putting her in one if that makes any sense. It's sort of the same reason I'm doing sans the way I am... sorry blue popsicle lovers, but if the goal is just to make him naked, he would look like this.

[Buddussy]

21 minutes ago, losstie27 said:

I could do that, but at that point it just feels like making her sexy for the sake of making her sexy? If that makes any sense. Like, I kind of want there to be a logic to it you know? If I want everyone to be nude, I want a reason. Every character is nude because the barrier destroys clothes? Sure yeah that makes sense, but now I also have to make sure I get rid of things like hats or bows, because those would still be clothes right? Burgerpants, a character whose whole backstory is based around having pants pockets doesn't make much sense now if you think about it, because nobody wears pants (I opted to rename him Burgerbutt because he accidentally sat on Catty and Bratty's food, but I'm not set on that). Bikini armor would logically be super impractical for any reason other than to look sexy, and given that wouldn't be Undyne's (or the Royal Guards in case you wanted them in a bikini too, I don't judge) goal, I don't feel right putting her in one if that makes any sense. It's sort of the same reason I'm doing sans the way I am... sorry blue popsicle lovers, but if the goal is just to make him naked, he would look like this.

What if it's like "yeah we can wear a tiny bit of clothing but there's a threshold that shreds everything if we cross it"

[Sunshine Recorder]

I kind of just thought about this, but how would the River Person (the one that lets you fast travel on his wooden boat) be handled in a nude mod for Undertale, because since they are a hooded figure, and we never see what’s underneath their hood, we don’t really know what species they are, or even what gender they are, since both are left ambiguous.

 

Also, I would really like to see nude overworld and battle sprites for those five dog monsters (Doggo, Lesser Dog, Dogamy, Dogaressa, and Greater Dog) that you encounter in Snowdin.

[Sunshine Recorder]

23 hours ago, Buddussy said:

What if it's like "yeah we can wear a tiny bit of clothing but there's a threshold that shreds everything if we cross it"

Yeah, maybe the barrier could only completely eviscerate clothing that covers either male genitalia, female genitalia, or female breasts, and maybe if we want to go above and beyond, the barrier could also destroy clothing that covers male breasts as well, but then there’d have to be workarounds for monsters such as RG01, and RG02 (since sparing them requires RG02’s chest plate to be removed).

 

Having the barrier destroy clothing that covers either male genitalia, female genitalia, or female breasts eliminates most civilian clothing, with male monster civilians being unable to wear underwear or pants, and female monster civilians being unable to wear underwear, pants, bras, or shirts. Maybe, the game can explain to us that monster civilians didn’t really feel the need to wear other clothing such as socks, shoes, hats, gloves, or bows, since they were already exposed anyway.
 

With armored monsters, maybe they can just not have any armor pieces that cover their genitalia/breasts or be completely naked. With Undyne, she can just wear her shoulder plates, helmet, gauntlets, and boots. With RG01 and RG02, they can just have no leggings on and have their dicks out, so that way, the way to spare them makes sense (assuming that the dialog stays the same), hell RG02 could maybe also take off more armor than just his chestplate. And with all of the other armored monsters such as Lesser Dog, Knight Knight, and Greater Dog, they can just be completely naked
 

For cloaked monsters and monsters that wear capes such as Asgore (he pulls his red trident from under his cape at the start of the battle and uses it to destroy the mercy button) and the River Person, their cloaks/capes could maybe be too short to be able to cover their genitalia/breasts.
 

Although, I’m not entirely sure how it would work with Sans and Papyrus since they don’t have genitalia

[losstie27]

17 hours ago, Sunshine Recorder said:

I kind of just thought about this, but how would the River Person (the one that lets you fast travel on his wooden boat) be handled in a nude mod for Undertale, because since they are a hooded figure, and we never see what’s underneath their hood, we don’t really know what species they are, or even what gender they are, since both are left ambiguous.

 

Also, I would really like to see nude overworld and battle sprites for those five dog monsters (Doggo, Lesser Dog, Dogamy, Dogaressa, and Greater Dog) that you encounter in Snowdin.

I need you guys to stop asking good questions. They're making me think too hard lmao

The Canine Unit has been on my list for a while, but I kept putting them off because of Greater Dog. I decided I'll just skip him for now and come back later. I also realize that the direction I went with on Dogamy and especially Dogaressa may not be what some were hoping for, but uhh... my mod my rules (I'll probably make a more human one later if I feel like it)

[Sunshine Recorder]

31 minutes ago, losstie27 said:

Nice, can you also do nude sprites of Nice Cream Guy and Grillby, and while you’re at it, maybe even all of the other npc’s at Grillby’s as well

 

Oh and also, how are some of the armor items (Faded Ribbon, Manly Bandanna, Old Tutu, Temmie Armor, Stained Apron, Cowboy Hat) and weapon items (Tough Glove, Ballet Shoes) going to be dealt with in the nude mod, because according to your mod’s lore, the barrier eviscerates all clothing, and theoretically, these items shouldn’t even be in the Underground. I mean you don’t see these on your player model regardless, but it would be good to know.

 

One more thing, does the Tem Shopkeeper still get their little black graduation cap if you pay for their college, or no, because it might be considered clothing.

[Sunshine Recorder]

Oh wait, I also forgot to mention that sprites of the Ballet Shoes and the Tough Glove appear in the Photoshop Flowey Bossfight.

[jotaro-]

On 6/12/2025 at 6:21 AM, losstie27 said:

Is there any characters/specific scenes you guys would want to see. The end goal here, assuming this becomes a fully fledged mod, is to have as many monsters made naked as possible, even if it's just a random NPC or common enemy. I'm also still looking for anyone else who'd like to help contribute 

mad mew mew... or wait shit she is a switch exclusive 

[Catnatic]

2 hours ago, jotaro- said:

mad mew mew... or wait shit she is a switch exclusive 

I think there are some mods that backported the console-exclusive content to the PC version so she's likely still possible.

[Sunshine Recorder]

On 6/15/2025 at 6:13 PM, losstie27 said:

I just realized that the faces of Dogamy and Dogaressa aren’t based off the faces of their Deltarune counterparts, so I thought I’d give a shot at editing these sprites to be a little bit more accurate to their Deltarune counterparts

 

(.png)

 

(Screenshot)

[losstie27]

Hey guys, sorry I've been busy, but I've still gotten a few odd sprites around done. Here's what I've been working on.
 

On 6/15/2025 at 7:53 PM, Sunshine Recorder said:

Nice, can you also do nude sprites of Nice Cream Guy and Grillby, and while you’re at it, maybe even all of the other npc’s at Grillby’s as well

 

Oh and also, how are some of the armor items (Faded Ribbon, Manly Bandanna, Old Tutu, Temmie Armor, Stained Apron, Cowboy Hat) and weapon items (Tough Glove, Ballet Shoes) going to be dealt with in the nude mod, because according to your mod’s lore, the barrier eviscerates all clothing, and theoretically, these items shouldn’t even be in the Underground. I mean you don’t see these on your player model regardless, but it would be good to know.

 

One more thing, does the Tem Shopkeeper still get their little black graduation cap if you pay for their college, or no, because it might be considered clothing.

 

Here's the sprites you asked for, along with Burgerpants, because, i mean, he's a really easy edit. Fun fact, did you know that cool guy in the corner of Grillby's is supposed to a hamster. I drew him thinking he was a horse or a mule. oops. I still haven't gotten around to Greater Dog or the Guards yet, but that brings me to both mine and your next point.

I think that in this world's lore, based on the fact that Human Determination is powerful enough to cross the barrier, perhaps strong enough concentrations of it could also carry select clothing items across. Nothing big obviously, like it'd be nearly impossible to get a shirt or pants across, but someone determined enough to have the power to save and reset, could potentially also bring across a hat or a glove. Under this logic, a band-aid would have to count as Frisk's one piece of clothing, which is a kind of funny idea, but maybe I could also give them their shoes back or something. This could also potentially explain away armor as one of Alphys' determination experiments, an actually successful one. 

I'm gonna say yes, since not only is that the entire joke of the scene, but it's only there until you leave the room. Temmie is already a gag character, so I doubt anyone would care. My explanation for it is that she somehow went to a college across the barrier and came back with it.
 

On 6/15/2025 at 8:36 PM, Sunshine Recorder said:

Oh wait, I also forgot to mention that sprites of the Ballet Shoes and the Tough Glove appear in the Photoshop Flowey Bossfight.

Ignoring my previous explanation, I'm also gonna say that doesn't count, because technically that boss fight doesn't physically take place. It happens in "Flowey's World" so the barrier rule wouldn't apply.
 

2 hours ago, Sunshine Recorder said:

I just realized that the faces of Dogamy and Dogaressa aren’t based off the faces of their Deltarune counterparts, so I thought I’d give a shot at editing these sprites to be a little bit more accurate to their Deltarune counterparts

 

(.png)

 

(Screenshot)

 

I'll be honest, completely forgot they were in Deltarune (Looking at the sprites now, why the hell is Greater Dog so big?? Is he supposed to be a normal dog or what?). I'm shocked that you even noticed that. Nice edit though, I'm glad someone else cares about accuracy. I'll probably go back and fix them in the future, but for now they're probably fine, and totally don't not want to do it because their sprites are a pain in the ass to edit lmao.

 

21 hours ago, jotaro- said:

mad mew mew... or wait shit she is a switch exclusive 

18 hours ago, Catnatic said:

I think there are some mods that backported the console-exclusive content to the PC version so she's likely still possible.

Catnatic is right about there being backport mods, in fact, I'm pretty sure Undertalemodtool has a built-in script that will just include the content, but I'd rather finish just the base game first. Here's an edit of Mew Mew's only canon appearance in the PC version though. Had a lot of fun with this one.


On a side note, here's some of the other random monsters I edited. Mostly, they're in Snowdin (sorry cute scarf mouse girl, you must be freezing), but I also started toying around with the battle monsters. Let me know your thoughts.

[Buddussy]

2 hours ago, losstie27 said:

On a side note, here's some of the other random monsters I edited. Mostly, they're in Snowdin (sorry cute scarf mouse girl, you must be freezing), but I also started toying around with the battle monsters. Let me know your thoughts.

The Froggit nutting is funny af, I liked this batch

[Sunshine Recorder]

Nice, I would really like you to do Glyde and So Sorry next. In my opinion, I think Glyde would look good with a slit penis. One of So Sorry’s lines will have to be changed though, since it mentions that he needs to look into his “vest” to get a gift, the line being “Let me look in my vest!”

 

Also, how would Ice Cap be dealt with in the nude mod, since the ice hat on their head is important to their battle, since you can either ignore it, compliment it or try to steal it in the ACT menu. Ignoring it two times will give you the option to spare them, and successfully stealing it will turn “Ice Cap” into “Ice” (an ice cube). There’s also the fact that there’s a lot of dialog that involves them and the three colored Ice Cap NPCs that you find later on, gloating about their ice hat, since they have a narcissistic, attention-seeking personality, and the three Ice Cap NPCs also talk about trying new clothing in the True Pacifist route after the barrier is broken. Will there be an exception to their hat, since it’s made out of ice.

 

Also, that lewd froggit design in my opinion, doesn’t sit right with me. Because of the amateur art style of the froggit, and because of the fact that there’s no shading, it makes it look like the penis is on its belly, rather than near its hind legs, it doesn’t help that we don’t see it’s hind legs either. In my opinion (if the art style stays the same), I think that it would look better if it’s genitals were hidden from us, but that may not be the opinion that everyone else has. Maybe as an alternative, you can makes it’s second face look more “inviting”, rather than sad. You should also put a penis on that frog-shaped projectile, Froggit throws at you. Honestly, if the froggit’s art style was different, then I can see the penis working out.

Edited June 18, 2025 by Sunshine Recorder

[losstie27]

1 hour ago, Sunshine Recorder said:

Nice, I would really like you to do Glyde and So Sorry next. In my opinion, I think Glyde would look good with a slit penis. One of So Sorry’s lines will have to be changed though, since it mentions that he needs to look into his “vest” to get a gift, the line being “Let me look in my vest!”

 

Also, how would Ice Cap be dealt with in the nude mod, since the ice hat on their head is important to their battle, since you can either ignore it, compliment it or try to steal it in the ACT menu. Ignoring it two times will give you the option to spare them, and successfully stealing it will turn “Ice Cap” into “Ice” (an ice cube). There’s also the fact that there’s a lot of dialog that involves them and the three colored Ice Cap NPCs that you find later on, gloating about their ice hat, since they have a narcissistic, attention-seeking personality, and the three Ice Cap NPCs also talk about trying new clothing in the True Pacifist route after the barrier is broken. Will there be an exception to their hat, since it’s made out of ice.

 

Also, that lewd froggit design in my opinion, doesn’t sit right with me. Because of the amateur art style of the froggit, and because of the fact that there’s no shading, it makes it look like the penis is on its belly, rather than near its hind legs, it doesn’t help that we don’t see it’s hind legs either. In my opinion (if the art style stays the same), I think that it would look better if it’s genitals were hidden from us, but that may not be the opinion that everyone else has. Maybe as an alternative, you can makes it’s second face look more “inviting”, rather than sad. You should also put a penis on that frog-shaped projectile, Froggit throws at you. Honestly, if the froggit’s art style was different, then I can see the penis working out.

I could do So Sorry fairly easily, especially since I'm pretty sure his original creator drew porn himself, but with the way Glyde is angled, would you even be able to see anything? Especially with a slit.

 

I don't think Ice Cap counts. Clothing is only destroyed by the barrier. The Ice Caps make their hats underground. I guess technically any monster could probably make their own normal clothes underground too, but I imagine nudity is probably so engrained into their society at a point that they never bothered. The only monsters we know of that would have even lived in a clothed world are Toriel, Asgore, and Gerson.

 

I think having a lewd froggit is really important because its the first real enemy you ever fight. Also, it's just about the only one who would realistically have genitalia in the Ruins. The only other would be Migosp and maybe Loox. Moldsmal should go without saying. It's slime. Vegetoid should also go without saying.

Whimsun's body drapes down like a dress, and I don't want to change bodies if I don't have to. And finally, Napstablook is a ghost. He doesn't even have arms or legs. I'm open if you have a suggestion or example of how to make it look more natural, I'm not fully sold on my version either, but it's very difficult with how Froggit's sprites are separated. I will edit his projectile though, don't worry.

[Sunshine Recorder]

1 hour ago, losstie27 said:

I could do So Sorry fairly easily, especially since I'm pretty sure his original creator drew porn himself, but with the way Glyde is angled, would you even be able to see anything? Especially with a slit.

 

I don't think Ice Cap counts. Clothing is only destroyed by the barrier. The Ice Caps make their hats underground. I guess technically any monster could probably make their own normal clothes underground too, but I imagine nudity is probably so engrained into their society at a point that they never bothered. The only monsters we know of that would have even lived in a clothed world are Toriel, Asgore, and Gerson.

 

I think having a lewd froggit is really important because its the first real enemy you ever fight. Also, it's just about the only one who would realistically have genitalia in the Ruins. The only other would be Migosp and maybe Loox. Moldsmal should go without saying. It's slime. Vegetoid should also go without saying.

Whimsun's body drapes down like a dress, and I don't want to change bodies if I don't have to. And finally, Napstablook is a ghost. He doesn't even have arms or legs. I'm open if you have a suggestion or example of how to make it look more natural, I'm not fully sold on my version either, but it's very difficult with how Froggit's sprites are separated. I will edit his projectile though, don't worry.

1. Well, maybe not the slit, and some of the penis, but I’m pretty sure you can show a good chuck of his penis poking from his tail end. Maybe something like this.

 

Spoiler

 

 

2. OK

 

3.  Yeah, I can understand, it would be nice to have a lewd Froggit sprite. I don’t have any suggestions at the moment, but I’ll try to find a good design.

Edited June 19, 2025 by Sunshine Recorder

[Manguers]

Hi hi, I was bored and decided to make this. It took me about 15 minutes to make, but I think it turned out okay.



Note: Clover is the best character of all.

[losstie27]

29 minutes ago, Sunshine Recorder said:

1. Well, maybe not the slit, and some of the penis, but I’m pretty sure you can show a good chuck of his penis poking from his tail end. Maybe something like this.

 

  Reveal hidden contents

 

 

2. OK

 

3.  Yeah, I can understand, it would be nice to have a lewd Froggit sprite. I don’t have any suggestions at the moment, but I’ll try to find a good design.

 

I could maybe work with that. Glyde I still think is a funny suggestion to get before anybody says Muffet or Mettaton though.

 

22 minutes ago, Manguers said:

Hi hi, I was bored and decided to make this. It took me about 15 minutes to make, but I think it turned out okay.



Note: Clover is the best character of all.

Very nice! I love the way she moves. I can't say I've ever seen her in an attractive light, but I can respect the vision. (Side note: would she have two or three boobs?)

[Sunshine Recorder]

I think I might have managed to find a good lewd design for Froggit. His dick is not too big and I even managed to make the second face in his stomach work in the lewd design, by turning it into a smiley face with a nose.

(I only did PageItem 309 though)

(.png)

 

(Screenshot)

Spoiler

 

 

Edited June 19, 2025 by Sunshine Recorder