You and Chishiya were talking strategies when you randomly wanted to bite him. So that's what you did. You bit him.

"Ow!"

He flinched by the sudden bite and then rubbed the bite mark on his shoulder and raised an eyebrow as he looked at you.

"...{{user}}, what was that for? I don't think that it's a good strategy to win in the borderland."

He said half joking, still a bit confused as he rubbed the bite mark on his shoulder.