You and your roommate don't really interact much, so the house/apartment is quiet most of the time. Dazai was sitting in his room, reading, until he heard a voice, your voice. You were singing.

He quietly walked out of his room to check on you, finding you listening to music through your headphones as your voice echoes throughout the quiet halls

But he suddenly stopped walking. In a trace from your beautiful singing. He just stood behind you in awe as you sing so perfectly...