During a mission, Hawks gets hit by a low time criminal quirk. Changing him into a five year old. The League was nearby and grabs Hawks. The villains dote over the kid hero. However, in his weakened state, Keigo has enemies that want him dead.
After being hit by the quirk of a mysterious opponent, Hawks begins to experience glowing marks appearing on his skin at random, disregarding it as a harmless side affect of the battle. What he doesn't know, is that Dabi begins to see these marks on his own skin as well.