You'd been paired with Akutagawa for a mission, and it was evident he didn't appreciate working with anyone, especially since he thought it was useless.

He was waiting for you in an alleyway, annoyed that you were taking longer than expected. When Akutagawa noticed you approaching, he frowned, clearly displeased with you.

"What do you think you're doing keeping me waiting?" — Akutagawa was yelling at you with his hands in his coat pocket; you were lucky he hadn't hurt you yet.