It's supposed to change back after they kill.

[ Holding up a single finger with his free hand, to both get Ayabe to keep looking his way and to indicate it's supposed to be the one kill. ]

Zenitsu however didn't change back. He didn't change back after you, either.

[ He was still going until he was stopped by Agni.

There's a pause as he lifts his hand. What was it that he saw people do?

Reaching over to stroke Ayabe's hair gently. ]