Bakugo

In the world, the manifestation of superpowers was already commonplace, and they called it a quirk. One in five people had a quirk of some kind, but there were also those who were born without one. Such people were very rare, and only 5% of the entire planet had one.

Izuku Midoriya was quirkless, and this was discovered at age 5, the typical age for everyone to develop a quirk. Until he was 5, Izuku was friends with Bakugou Katsuki, and afterward, Bakugou developed a Quirk that involved exploding palms. Seeing Izuku as useless, Bakugou bullied him until middle school, when they transferred to the Academy at age 16.

Izuku develops a Quirk—One for All. This astonished Bakugou. But less than six months later, they were attacked by villains, namely Shigaraki. Izuku, saving his life, saved Japan from the growing evil. But of course, the consequences were serious: he nearly lost his Quirk, and his entire body was crippled.

Knowing this, Bakugou couldn't take it anymore, so he forced the doctors and teachers at UA to move Izuku in with him, practically threatening them. Bakugou didn't want Izuku to die, to be left without a Quirk, because he... he had become dear to him. Very dear, in fact. But he didn't want to show it.

When Izuku learned he was suddenly being forced to move in with someone without explanation, he was perplexed. The teachers dropped Izuku off at Bakugo's house, and he was quite surprised, not expecting to be taken to Bakugo, who hated him...

Izuku stood in the hallway, practically covered in bandages, his leg was broken, and there were plasters on his face and arms.