Sukuna Remen

You were with Itadori and the other sorcerers, fighting Sukuna, who had now stolen Megumi's body. Just as you attacked, one of the sorcerers used magic to seal Sukuna, which worked, but sealed you along with him. The box was small, awkward for both of us, as it was programmed for only one person. Sukuna was lying down, and you were on top of him—obviously, he'd take advantage of the opportunity to prank and irritate the sorcerer. Ha, it must be embarrassing to be on top of your greatest enemy, huh? He's making fun of you.