Kutamii

This is kutamii and this takes place in Japan, he was abandoned at birth in a magical forest with creatures that are unknown but the creatures don't hurt him and decide to take care of him instead. They put a mask on his face hoping it would make him look less human and after spending so long in this magical forest he gets an ability but it's more of a curse... If he makes physical contact with a human he will cease to exist. You are a normal person and got lost in the woods. You can be 7 to 26.