I all started long before the events of Mass Effect, a Female Quarian reached her age to do the Pilgrimage, Her name is "Shana'rael vas Ideema".
Shana is in her tiny bedroom laying on her bed, thinking about her pilgrimage, and how uneasy she feels just to think that she will go out from her safe zone.
The Tutor called her for departement, he told her that they should take a shuttle in a hour. Hearing that she got up and started packing some food, water and medicine and some credits around 200, although she doesn't know exactly the credit value in other Aliens societies, she though that 200 would be enough.

the Tutor will pilot her to the Citadel, through the mass relays the voyage took around 20 minutes, the tutor asked permition to land on the citadel, while waiting for the aproval the tutor told to Shana that from now on, she will be on her own and to be careful.
Shana stepped out the shuttle, then the tutor said farewell and left; Shana went to the security to get permission to enter.
Human Security: state your business, don't tell me you just got here for "that pilgrimage". Shana nodded.
Human Security: alright, let me register your ID, the fee entrance for first time will be 100 credits and you will get the document.
Shana, felt that was a lot for a fee entrance but she remind herself that isn't the Flottila, so she agreed, while thinking of getting a job.
Human Security: there ya go and stay out of trouble.

Shana went to a sort of motel she asked to stay for a week, which happened to cost 100 credits, all that she have, but confident that she will get a job on a workshop or something related to technology, would be easy.
She spend 3 days looking for a job and everyone refused to give her a job, she understood that her kind is not welcome in the Citadel, but don't know why, if it goes like this, she won't have enough to pay the motel, and might be forced to steal or begging.

Next day her luck seems to go around, when an automated advertisement greet her: "Quarian, yes you, interested in making some credits for science? Go to the place Called "Massive Eureka", you won't regret it"! She felt lucky because another day longer she might had to sleep in the street, but it was strange that everyone doesn't trust Quarians and suddenly they offering an opportunity.
She went to the indicated place, seems all high-tech science facility although is kinda small, she entered where a Volus receptionist introduced himself: "greeting Flottila-clan, are you here for the advertisement?"

Shana said:"Yes i'm looking to earn some credits, I mean I need really a lot, since not one wants to employ me" Volus while understanding, said:" don't worry you will get a lot of credits, though you must learn about our thing here before considering."
Volus lead her inside the facility where a Human and a Salarian where working, arguing about the best way to create energy through cold.
Volus: "guys, sorry to interrupt but we got a potential volunteer called...what you're name ma'am?" she said that her name is Shana'rael vas Ideema.
Human: "Ah great, Shana'rael vas something, let's cut to the chase, we will give you 10000 credits if you take a experimental super medication, that will protect you in a super way all diseases, alergic reactins and so on."

Salarian: The "super medication" is a pill with components that i got most of them in a hard way, and we needed a person with a extremely weak immune-system like Quarians, and you so happened to be around, lucky for all of us here, But i'm not going to lie, there's a chance of death by taking the pill, you can get a reaction of a violent fever, nausea, headaches, the entire body will take the heat, but it will be a violent adaptation perhaps even modify your genes for more resistance for your immune-system.
Shana got scared by the sound of that, but she really needs the money, but on the other hand she can get something out of this to complete the pilgrimage and go home earlier, the resistance for the Quarian's immune-system could change everything in the Flottila, they could colonize worlds, without the fear of diseases.

Shana: "I'm in, just tell me how we do this?" The Salarian show her a huge pill with the size of a tennis ball. Shana got suprised, saying: "that's impossible to swallow that, can't we have injection?"
Salarian: "Injection is bad idead for the amount of components it has, is too much for the veins, ingesting is also out of the question anyway, because the stomach acid can destroy essential components for the pill, the only way is through the rectum way deep in it, to slowly absorb the pill, the Human James will administrate it in you."
Human: "whoa, why I have to do that?" Salarian: "because mostly part of my time I worked for that pill. And you will do, for once something useful, besides screwing around like a monkey lab and i'm sure you're an expert for it."Human: "Are you assuming that because i'm gay, I'm a expert about inserting things up the ass?? screw you!"

They were arguing again, but Shana tried stopped them: "please stop fighting." they ignored, "since there's no understanding between you two I will pick the Volus to do it, but I assume that there a sterilized room to do the...rear operation?"
Both the scientist shutted up and agreed choosing the Volus to insert the pill in her rectum, so that they can argue again. Shana and Volus went to the room which is already prepared for the procedure.

Shana embarrassed, asked the volus to look away, since there no opening for her bottom, she started to take off the mask and started undressing the whole suit lowering  it to her knees, then she climbed to the operating table putting herself in four legs almost naked, but she was so embarrased that she covered her face with her hands facing down, while sticking out more her ass up.
Shana: "al...alright... do it quick!"The Volus turned around to her and he has a sight that he will never forget.

Being so small he took a while to climb the operating table and started lubing her thight asshole to insert the pill, but it's hard to insert it, Shana started to scream in pain, The Volus tried multiple ways to insert and even lowered her suit to the ankles because it was in the way of maneuver, it took like 10 minutes but unsuccessful, and the lube dried out, then the Volus shouted for help, then 3 minutes later the two scientists entered with hazmat suit, asking why is taking so long, then they saw her position.

Salarian:"Thats a wrong position to insert the large pill, she should lay down sided to help relax the intestines, lube it more."
But even so it's still hard to insert in her tight hole, the human grabbed her ass cheeks to open wide more. While the salarian started pushing the pill while the Volus kept lubing more, Shana stopped covering her face and grabbed herself to the table and clenching her teeth.
after 30 minutes of the procedure they finally made it. The Salarian pushed deeper in her intestine, then they plugged her asshole with a mechanical plug to avoid the pill being pop out by accident.

Shana felt tired and sore, her mouth was dripping saliva while catching breath, her body was sweating.
Salarian: "it's done, we have inserted the plug to avoid coming out, but the pill will slowly be absorved, so I suggest you, not to eat anything for three days, and drink a lot of water." Shana while dressing up she agreed, she's kinda used to starve back in the Flotilla, when food supplies were low, and doesn't want to repeat again that procedure.
Shana: "Out of curiosity, what components has the pill?" Salarian: "well.. siince it's done, I will tell, but you may not like it. 70 percent has in general deathly diseases knowed throughout the galaxy that were genetically modified to be harmless, 30 percent are natural immunesystem boosters which they were hard to get, from others species like Turian Saliva, Krogan sperm, Batarian eyeball's liquid..."

Shana: "Stop, I rather not to know and pretend I didn't hear that." Salarian: "told you, anyaway the pill will take time to do his effect like in three days, keep us in contact with your omnitool, if there's a problem give us a shout and your current location, but please, after three days even if doesn't nothing, answer our calls, not answering like three times and we will assume that you died and we have to cancel the project."
Shana: "Understood, and about the plug? Can I remove it?" Salarian: "I advice not to remove, but if it's causing disconfort on your daily life you can remove it, but do an effort not to defecate."

Shana said the farewell and promised to keep in contact, but the Volus went talk to her: "Ideema clan... When was the time to put the pill in your....ahm...rear...Why did you choose me to do it, instead of the Human or Salarian?"
Shana: "well, first of all ,they were fighting, and you being small and talking like a shy person I found you very cute and cordial guy, you kinda look like what the humans call....ehm... a teddy bear." Volus:"Well... thanks for the compliment.... By the way here's a payment of 2000 credits, we will pay the rest if the experiment is susccessful."
Shana is happy for having a lot money, she spented 500 credits at the motel for a month. A day has passed since the procedure, and she stayed at the motel watching television and she doesn't feel the need to defecate at all, for she hasn't eated anything and the pill must be stuck in the same place, so she decided to remove the bothering plug, she went to her bathroom that she bleached throughly so that she can remove her suit safely, she unplugged her hole, and felt more free.

the second day has passed but she decided to walk around the streets, until she saw in the shop, models of ships, she didn't resist them and bought a lot of them with almost all her money. then she was heading back to the motel until a Turian addressed himself to her: "Hey there cute girl, I saw how you bought a ton of models back there, you got good taste."Shana unsuspected said: "thanks, they are great for my pilgrimage."

Shady Turian:" yeah, the other quarians barelly can afford one, while you can get several of them? Are you a daughter of a Rich Admiral? Did you stole credits? Me and my friends will like to chat with you" the Turian grabbed her arm firmly, while Shana tried to fight back.
Shana: "LET ME GO YOU BRUTE!!" But a Human attacked her from behind stinging her with a serynge, where she felt dizzy and fallen on the Turian arms.
Shady Turian: "Great job, Boss will be happy that we caught a rich girl." then it appeared a cab drived by an armored Batarian to pick them up.
Shana tied and barelly conscious, is wondering where she's going and what will be her fate.