i assure you guys who are waiting on the YCH-s, they are currently being worked on. i, unfortunately, have lacked so much motivation and fell head first into D&D ideas. i will be working on them, and post them by the end of next week 100% promised.
Syl realized they were a changeling at the age of 10. They were raised by a human woman who loved them, and still does, but hasn't seen them in years
when he (was in human form, so "he". goes by whatever pronoun fits their current form, but in themself identifies as they/them.) ran away in confusion, his hair bleaching before his eyes, his skin growing blue-white in color, he ended up in a cave as a carnival passed through. Seeing the young (they didnt know what he was) changeling suddenly becoming a human, they asked the changeling to join. Syl was with a traveling circus for years, never treated awfully, but was very much a freak-show with other beings that were weird and different. They were given books and learned Elvish during their travels, and in addition, they became a bard, learning to play a lute, a violin, and a flute. when Syl turned 15, the circus managed to find a Mimic. Syl ended up charming the mimic, who over time became like a pet. Syl isn't necessarily educated, but is very social and has had a relatively decent upbringing. Doug, the Mimic, learned to understand common, and is now the designated pet of Syl, who is the only person Doug will let go of voluntarily (Mimics are very adhesive when in object form). Their performance is that they play a song or two and at the end, jump-scare the audience with their true appearances. its a decently popular show, and has an off season where Syl and Doug will do other jobs disguised as others, sometimes a seamstress (using mend, mage hand, etc) and sometimes as a bar tender (Doug as a hat). if any fights or otherwise occur, Syl is honest with the Circus headmaster, but because they both change shape, they get away very easily.
They left to go experience the world, which is how they are adventuring.
in addition, Syl would have met another changeling while traveling with the circus, but didn't get to talk very much, because they were just passing through. this knowledge soothes him a bit, though, knowing he isn't alone as a changeling.