Senpai counterattacking - woohoo!
This is the second time he's grabbed Nagatoro's hand & pulled her out of a crowd (the first was when she was overheating at some venue, can't recall the chap, tho). What's even better is that, while the hand-grabbing was kind of spur-of-the-moment, Senpai's ability to stay calm & actually come up with a counterattack strategy while Nagatoro is actively teasing him is very impressive progress.
Go on, Senpai. Get her ovaries to tingle, ma dude. Fight-o!