Nanami makes a comment about his boring repetitive life and Gojo tells him to "get a thickie for a quickie, it'll change your life" and that night he sees you at the bakery and knows in that moment that what Gojo said was only an understatement
"Get a thickie for a quickie" shut up that's literally the best line ever
And you're so right. Nanami wouldn't stand a chance if he saw you that same night, his mind going straight to what Gojo said earlier in the day. He'd see your tight clothes that hugged your curves and he would feel the urge to trail his fingers along the hills and valleys of your body. He'd immediately envision you in a different scenario, legs pushed towards your shoulders, your sweet round face twisted in pleasurable agony as he thrusted into you over and over, giving you everything he has, letting all those petty frustrations melt away through the feel of your soft skin against his and you'd be so perfect like that, a dessert begging to be gobbled up.
And suddenly the cashier gets his attention and says that they'll be closing in five minutes, and Nanami sees you taking your pastries out of the corner of his eye, and suddenly he realizes that he wants something more than baked goods.
