The perfect children

When All For One "rescues" two preschoolers from danger, they become his successor's "little brothers" and grow up being frustrating little chaos gremlins. One has the personality of an unstable bomb, while the other is a master manipulator. What happens when the League of Villains unleashes their chaos gremlins on UA's hero course?

Or...

Izuku and Katsuki grow up in All For One's care and happily wreck havoc on UA.

Note: I do not own the anime this is based on or the characters. The pictures are all from Pinterest.