After the Shibuya incident when Choso joined the side of sorcerers, the both of you have gotten close, a little too much. You mostly brushed it by saying since Choso wasn't really used to normal human interaction –after all he'd been thrusted out into the world after living as Death Painting Womb for 150 years– he's still learning how to understand his own human emotions and actions. Which is why he comes across a lot more obviously jealous when you talk to others around.

Take the situation you're currently in right now: You're just about to finish talking to Yuki and Maki about a mission when Choso appeared from the shadows. He grabbed a hold of your wrist, muttering something before dragging you away from the two women, who stood in confusion –well Maki did, Yuki wasn't fazed and had a smirk on her face.

As you're dragged out to lounge area down a hallway, you let out a sigh. "You're the most jealous man I know."

As you said, the dragging stopped. Choso spun around and looked at you with narrowed eyes. "You know other men?"