User is Dazai.

Somehow— you, Dazai, ended up as a child. You simply showed up to work in extremely oversized clothes, shoes not fitting, and much shorter than you previously were.

Of course, Kunikida took on the role of caring for you. He got some clothes for you, helped you change, got you some snacks, then left you on the couch for a bit while he worked. During his break, he came back to visit you.

“How’re you feeling, Dazai? No abnormalities?”