Midoriya for the headcanon thing !
sexual orientation headcanon i always thought of deku as pan!
gender headcanon tbh i headcanon her as a trans gal. partially for kinda dumb reasons but ye.
mental illness / neurodivergent headcanon i think of deku as autistic, tbh. she’s def also got anxiety, imo? idk about anything else tho.
1. Deku only comes out to people she super trusts, and i think uraraka and tsuyu already know. kacchan knows too, and loans deku some of his old clothes (coughs i also hc kacchan as a trans guy) ((edit: totally forgot to say that i think iida’s also in this list WHOOPS))
2. i like to think 13 is deku’s other favorite hero besides all might, due to his specialty being helping other people.
3. DAYDREAMS A LOT, especially in class, which frustrates her a lot cause she WANTS to pay attention