okay so depressing backstory for music au: nancy and ben are the absolute worst stage parents in existence. the "probably vicariously living their dreams out through their kid" kind. elliot, pre-transition, and becky get shoved into a girl group put together by the annex at the age of, like, thirteen. you can imagine how well this went for elliot and becky's mental health.
fast forward a few years, where elliot, like canon, was pushed into drugs etc (and came out just before not so coincidentally) and becky was horribly traumatized by various things growing up in the industry and with parents who are the absolute worst. cue becky, when their parents want to announce the continuation of the group past the twins being eighteen, doing as she does in canon because it's just. she's that fucked up over it. elliot handles it.... well. (not) he moves into a tiny apartment bc he refuses to deal with his parents anymore and almost quits music entirely bc it cost him his sister.
(of course, one day he's visiting a music store to look at some of their instruments when he hears a bitching guitar solo and an even more awesome voice and meets sasha because he finds himself playing along despite it being a completely original song. sasha drags elliot home with her where he is promptly adopted by frank and the rest of cottonwood records and that's how type two twins is born. and then on their first tour when they're opening for someone, the other opener is marco. you can guess how that goes.)