Emergency Guy Talk
The day after the discussion with Shanna, Vincent needed to talk to someone. It wasn't as if he and Kristoff had had the typical brotherly relationship, and certainly not in the context of being Americans, but he couldn't think of anyone else to bring this particular situation to. Even if they'd pointedly tried to avoid talking about Vincent's sex life in the past.

They'd been scheduled for a science lesson anyway, so Vincent is expecting his brother to be available when he arrives at the lab. He's not quite distraught, but he's clearly uneasy.