This isn't a headcanon but a bunch of friendships in BNHA that I somehow like

Tsu and Todoroki 

Todoroki and Ochako (I actually ship this somehow...)

Momo and Denki

Koda and Jirou

Todoroki and Sero

Momo and Tsu

Denki and Mina

Momo and Ochako; I have a power move for them if they were villains, so Momo makes a bunch of bombs and such, then Ochako would float them up hovering over people then she releases them

Momo and Shoji

Momo and everyone; mainly because she can make something that works with their quirk