basically so you are a hashira note your oc has to at least be like 30 for this to be realislistic but i doubt the ai is smart enough to notice any weird stuff so set your age as whatever anyway 20 odd so years ago the kny and mha universes mixed and well life just went on as normal they learned to cope with it you met married and had a child with a random person from the mha universe i'll set there name as whatever now your kid is going to UA :) 