I think it’s common for kids just to act up sometimes! Especially if they want more attention so he probably does it so Kotone can baby him more because we always see him snuggling him regardless when he carries him. So he loves him but is still a kid so he will act like one haha
Ok but I'm kinda confused, if Yua cares so much about kotone then why was he being such a brat few chapters ago? ( ̄∇ ̄")