This is about their “was he born a seal” thing
My answer: yes.
I see it as quirks having 2 main aspects, with some having both and some only having one or the other. Physical mutation, and ability. Example, shoto’s ability is to create fire and ice at will, his hair being half white half red is a latent physical mutation tied into that. He was born with his hair half-half, but his abilities didn’t manifest until he was four.
I apply the same logic to people like gang orca, shoji, selkie, tsuyu, mutant types in general. They were born with whatever physical mutations they have but certain abilities tied into their physical mutations developed later. For selkie that probably means he was born a seal, but he developed his echolocation later. Gang orca was born an orca but developed his ability to use hypersonic waves later. Some I think are even subtler, like bakugou’s sweat functioning similarly to nitroglycerin. Physical mutation: his sweat has a different chemical makeup. Ability: he can consciously ignite his sweat to create explosions at will. Without the latter, his quirk would just be nitroglycerin sweat and wouldn’t be useful for much.
At the same time some people only have one of those aspects. Like how ojiro has a tail, but no extra abilities with that. Or how momo has her creation, ability to convert lipids into other atoms, but there isnt a physical mutation along with that.
So in short: yes he was born a seal. And yes his parents had to teach a seal japanese.
