Jepp, Sakaki turned out to be a total arse. Not trying to help his "best buddy" at all, but to get in touch with cute breast girl. And she turned out not to be that naive either. "He's got a nice face, but he's kind of an ass, huh?" Savage, but on the point. It's her kind way of telling him "I know you're after my ass. I'm not interested. Stop interfering and fuck off." It's obvious, that sempai is shy and those kind of questions will invite stupid answers. Sakaki tries to turn things awkward between those two and everyone noticed except sempai. For what reason? It obviously does more damage than good. The protagonists got in a fight.
It let's sempai look like a wuss (that he is), and himself as a confident stallion, just by being annoying. First thing, when trying to hook up with a girl, establish yourself in her conscious. How? Somehow! It doesn't matter, as long as you don't turn into Hannibal Lectar in her mind. Everything from diligent to bad boy is good.
EDIT: Okay, Okay. After reading the last two chapters again, I have to admit, there is a chance, he wants to get his buddy laid. (Just judging from his expressions.) But he still is a destructive force and a hinderence and I'm not convinced he is innocent. In real life his approach would mean what's written above. He's greeting his friend, while pointing a gun at him.
