seto is a fucking enigma... how can someone be such a wimp and such a chad at the same time? truly unfathomable
Remember, he's a traditionalist when it comes to relationships, like Senpai over in Nagatoro. There's no doubt about his love for Anna, but like his buddy, Inuyama, Seto wants to go through the proper motions to get to the Promised Land.
Remember that the reason why Anjou-san fell in love with Seto in the first place was that he defended her from the boys who were calling her the "School Bicycle," i.e., everyone gets a ride. If he was to treat her like that, he'd be a giant hypocrite.
But he recognized that Anna was hurting over the fight with her Mom, so cue Chad Seto and off to the beach they go...