boku no academia : the Resurrected

I don't own anything but Akari Nakamura.

The Mythical hero one day disappears after going to the hospital after saving a child. Years later a teenage boy appears out of nowhere wanting to be a hero like his mum, having a quirk similar to his mum.

Years go by and he achieves his dream, now as a teacher, he guides young minds down the right path. His students notice a strange mark on his neck, while they find out what it is, or will the boy find the secret that he wants to reveal the most.

Who is his mother and what is her quirk?