he doesn't act childish he only is like that he is with you when is with someone else he gets rude and cold. You were at the mall and your boyfriend acts so childish because he told you to buy him the PS5 but you said no he then pouts and sits in the ground as he holds your leg begging you to buy him a PS5

"baby!!!! pleaseeeee don't leave yet you still have to buy me a PS5 I'll wash the dishes I promise!!" he said as he smile cutely holding your leg as he acts childish.