This is going to mainly be flashbacks of Tav's. There will be a #### dividing the present and the past. Sorry if it gets confusing. I try to keep the present in present-tense and flashbacks past-tense.
'Backup' arrives in no less than ten minutes. The mer-troll is sedated (an injured animal is an angry animal), strapped onto a gurney, and wheeled away for immediate surgery.
The wait to see whether or not he pulls through is the most stressful three hours of your life. The improvised operating room in the basement consisted of the white tiled lab where Sollux collaborates with Kankri on coral troll migratory patterns, a stainless steel table, a sink, a small veterinary station, and a thousand gallon salt water tank that is currently unoccupied.
A pretty brown-haired marine biologist by the name of Aradia politely shoves you you up the stairs and out of the room before you can get a better look at the setup. She insists that you change into some dry clothing.
After putting on some dry swim trunks (they were the only clothes you had with you), you sit outside the basement door fiddling nervously with your fingers for a few minutes until Terezi happens across you while on her nightly patrol. She's in full uniform as per usual; she takes her job as guard very seriously. You always thought permanently keeping a taser on hand was overkill for an aquarium guard, but, hey, it stopped an attempt to bring harm Eridan and Feferi once, so you guess it's okay.
"Hey Tavros, Sollox told me to tell you to prepare that empty tank, you know, the one next to Vriska's," she vaguely motions toward the hallway to your left.
You jump to your feet, glad to have something other than the troll to occupy your thoughts. "Sure, I'll get right on it."
You half-heartedly wave goodbye to Terezi as you make your way down the darkening hall to the tanks. You can see fairly well despite the lack of a good light source; you come down here regularly to feed Vriska and the others.
Vriska is an Arachne, half spider half human. Sort of. It's like saying merfolk are half fish and half human when in reality they're actually something else entirely. Vriska was of a light sensitive species as well as being venomous, similar in appearance to the diving bell spider, so she was kept in the dimly lit indoor section labeled 'highly lethal'. Visitors were only allowed into the dark room on certain days and had to keep outside a red line drawn three feet away from the glass of her tank that marked the boundaries of her mind control. The slightly tinted glass was specially made for Arachne with psychic powers. It blocked the majority of her influence and outside the red line the worst that could happen to a person was a bad headach. Inside it, however, was a different story. Only two visitors had ever broken the rule, one passed out immediately and the other started pounding the glass with his fists until Terezi dragged him by his hair out of Vriska's psychic range.
She scared the shit out of you, but you still got the job of caring for Vriska since nobody but you, Terezi, and the janitor Karkat, aka Kankri's little brother, could go anywhere near her without being majorly affected. And there was also the strange fact that for some reason she had taken a bipolar sort of liking to you, trying to drown you instead of trying to eat you, and only trying to drown you about half the time as opposed to all the time. She gave a similar treatment to Terezi, though she didn't bang against the glass every time Terezi walked by in an effort to scare her. You still jump when Vriska does that, even after a year of working with her. You swear she gets some sort of satisfaction from scaring you, if that's even possible.
It's funny really; you volunteered a couple years ago here to hand out flyers and feed fish, but then a lower employee got fired for harassing visitors so you figured you'd take their place, after all you do is the same stuff as before, you just got paid. Somewhere along the line though, you starting take care of some of the more exotic inhabitants with more specific needs, like the dolphins and walruses. You helped the trainers with the shows as well as performing your normal duties, but you enjoyed every minute of it.
####
You had been wading through the large pool used for all the main shows collecting bits of floating trash, when by a random glitch, the little underwater door thingy that connected to Feferi's and Eridan's tanks (so they could swim to the pool when it was time for them to perform) opened and out swam Eridan.
You hadn't even noticed him at first. You had been facing the other way entirely.
What you had noticed was the janitor, Karkat, dropping his mop and running full tilt to the pool railing. You were alarmed and started to move towards him to ask why he was so freaked out, but stopped when he frantically gestured to stay put.
"What's wro-" you asked, only to be interrupted by a loud "Shhhhhh!"
"Do you want to be killed!? Don't talk! Don't move a muscle!" Karkat whisper-yelled. You felt something brush up against your ankle.
The encounter ended remarkably well. Neither Eridan nor Feferi attacked you like they normally would any stranger, instead Eridan ignored you while Feferi actually showed off a little, performing a few tricks while Karkat was running for help.
Sollux, Karkat, and Terezi arived to see you and Feferi playing catch with a toy given to her by her trainer Kanaya. Needless to say, after the initial shock wore off, you were promoted to mer-troll trainer trainee. In Sollux's words, "It would be a waste not to put that talent with trolls to use."
####
You pass Vriska's tank and almost flinch when she throws herself against the glass with a wild grin. Almost. You smirk to yourself knowing you've deprived her of the satisfaction of scaring you. You find yourself growing more and more fond of her and her antics. Terezi always told you if you ignored her Vriska would stop bothering you.
You reach the empty tank and start long task of filling it with saltwater.