Bruce leaning into the whole airhead billionaire shtick at certain events, knowing that it pisses off Lex Luthor, who cannot prove it but knows that Bruce is not that dumb. For fuck sake, Lex knows that Bruce is a polygot, that he can follow physics equations, that Bruce literally aced his exams. Why? They shared a dorm room in boarding school. However, Bruce sees how much it winds him up so he really plays into it.
Bruce outs Clark as Superman while Clark is interviewing him and Lex. "I don't know why you two can't get along like you are now 😔 Superman, maybe Lex just wants to spend time with you 🤔 And Lex, babe, the robots are cool and all but you can't like throw them at Superman 😶 That's not how you make friends." Lex tells Bruce to stop, rolling his eyes. Bruce goes on a rant about how the butts match etc. Clark is literally sat so still, trying not to move.
Lex yelling at Bruce when he pretends to not have overheard a conversation Lex was having with an arms dealer in Korean and Lex is all "you speak fourteen languages, Bruce" and you got Bruce who is near tears over his puffing because he only speaks two? "I only speak American and English 😭😭"
Bruce giggling at some charity quiz show panel between Ollie and Lex, because he's so sorry but he doesn't know any countries? Like what are they??? Lex is screaming at him while Ollie hits the button so confidently going "Las Vegas".
Bruce sitting next to Lex on a plane (they're economising for PR) and he's fucking reading a book that's upside down???
Bruce asking Lex about the business finances, asking which company is "winning"? It was the day that LexCorp stock was tanking.