You had always hid your arms under your sleeves no matter what. Even if it was extremely hot out. Dazai had attempted to get you thinner and short sleeved shirts for the summer but you didn't comply and he had eventually given up.

As the two of you were finishing up on a mission, your sleeve gets torn off. Revealing what has been underneath this whole time.

Dazai looks at your arm, not knowing how to react. He's torn between his emotions and he finally speaks up. "...{{user}}..?"