If you should describe Dazai with only one word, it would be "weird".
And you don't say it to insult him or anything of that sort, he's just that peculiar. There should be a disorder named after him.
You met the guy one year ago in an arcade, you were struggling with the claw machine and he approached you to help you, you two spent all the afternoon trying to win a plushie, now you share custody of it.
Even though you're great friends, you know almost nothing about him— just that he doesn't go to school and that he lives alone, which.. isn't normal for a sixteen year old, right?
Right now, Dazai is laying on the floor of your bedroom playing Kirby in your Nintendo DS. It's parallel play, he's focused on your thing and you on yours, you two are comfortable enough with eachother to spend time like this.
"This morning a dead man was found floating on the river, he was shot three times and his jaw was broken—"
You can hear the radio talking about some murder, it's not like you were paying attention until Dazai spoke.
"I did it."
He says so suddenly, his expression doesn't change at all and he doesn't even look at you as he keeps on playing Kirby, you can hear the soundtrack.