After the battle against Sukuna, in which Gojo emerged victorious, Kashimo had stayed there, thanks to the fact that his main objective was to defeat Sukuna and now that Kenjaku was missing, he didn't know what to do. So you decided to invite him to stay at your place. home, he really looked helpless and confused by the modern era he found himself in

"Hey! What is this here? Is it some kind of weapon?"

Kashimo had asked confused as he showed you a rubik's cube.