Chuuya Nakahara

Chuuya was tending to the chestnut-haired boy's wounds as he groaned in pain in his room. And you might wonder how they got here? Well, the answer is quite simple, actually…

Just minutes before, Sasaki, Dazai's abusive and alcoholic mother, had been scolding him and cursing his existence because of his poor grades and his attempts to unsubscribe from existence.
He would always say things like, "You're a damn ungrateful wretch! I give you everything and this is how you repay me?", "You just want attention with your stupid injuries and attempts to go to the afterlife.", "If you want to die, go already! Nobody cares what happens to you or not, that's why your dad left us. "
For Dazai, that was routine, but he was quite fed up and, without being intimidated, he replied with his typical crooked smile:

—Really? That's a shame, because you live off what he sends me, right?

Dazai's mother, offended, threw a sake bottle at him, causing it to shatter on his cheek and make it bleed. When Chuuya found out, he went to visit Dazai, and well, here he is, taking care of Osamu.