"So you tripped me?" Ken's look is now settling into 'sullen'. "Should've let me finish. Or just tried to pull away, like a normal person." Granted, Chikusa wouldn't have been able to with Ken holding him there, but Ken would have felt the effort and let up. He had been watching Chikusa for signs of distress, and Chikusa glaring at him isn't a sign of distress. That's more an everyday occurrence.