LukasS
it would be a good option to give him a board of evil pieces (dxd), he would become the king and nejire the queen, his mother could become a bishop, eri could be the other bishop He wouldn't get much stronger, since he would become like a two-winged demon, which is weak even by bnha standards, but he would gain the resistance of a demon, and his lifespan would be 10 thousand years. It wouldn't be a very strong powerup, but it would give him a physique more compatible with the Devil Fruit and allow him to give upgrades to his allies. It would be interesting to do this without adding harem to the story, just continue with nejire/nejire