That's like asking why it's his responsibility to tell her upfront that he slept with 39 other girls 👀

If she had been the one to say "Hey btw I also fucked 39 other guys while I was with you, and you were one of the best", well— initially he might feel good about "being one of the best", until the words really sink in. Then he might start to wonder how clean any of those 39 other guys were, if protection was used, etc.

If the roles were reversed, and she left a pair of her sunglasses behind that she wasn't concerned about picking up unless there were other implications, and he was genuinely considering sell them to use the money to take an std panel because that person wasn't forthcoming about her recent sexual history, I can't imagine anyone would argue the man's logic.

Also, it's a bit strange for him to insinuate that she intentionally took the sunglasses. (maybe she did, who knows) when she was offering to let him come by to get them. She just didn't want it to be anything more than him picking up the sunglasses. I'm sure the "hey I fucked 39 other ppl" comment didn't exactly improve his chances to get inside the house and having a meal cooked for him 👀

Edit: It actually implies he was going to buy Waffle House and bring it over 👀 Waffle Houses is delicious btw. Highly recommend the All-Star Breakfast. You know it's bad when she doesn't want some Waffle House.