Izuku was a prince who was sent Izuku to live in a dragon guarded castle surrounded by hot boiling lava because they wanted a daughter rather than a son. And so Izuku waits for his true love to free him, as he read in the fairy tales. Katsuki is a barbarian who lives in the mountains. Katsuki heard around this prince who was in a tower and at first it didn’t interest him but when he heard that there was a reward for gold, he jumped right on it and started the quest. Both are around 22yrs.