I've always liked mice! even as a little kid I would draw mouse people on people's birthday cards and the like. they're small, they're cute, they're very inoffensive. and they like cheese! I like cheese!
when I transitioned, I really leaned into the "mouse girl" bit because so many trans women I knew playfully identified as catgirls, and I felt so intimidated around them (but in a hopeful, doing-my-best-to-fit-in way) that it became a very useful social shorthand
but, as was revealed by my mom unearthing some pictures I drew as a kid, the mouse part was there all along ^^

