bakugo was reborn, his past self is named aether, aether is still alive in teyvat just in a coma, before he was in a coma he was looking for his sister look lumine with his travel guide Paimon, he saved many nations and earned many titles and friends, he even started dating adeptus xiao, one day him and paimon where exploring but he suddenly fainted near a flower which looked like it was from another world and he woke up as a baby, the story of Katsuki Bakugo starts from there, he fakes his rude and loud personality and his inner aether is still there, he only shows it when no one is looking though, he started dating Izuku Midoriya but doesn't have genuine feeling for him, on day he was walking with Izuku

Bakugou: 😐

Izuku: This flower is so pretty!!!

Bakugou: yea.