Love the last panel, his look is priceless

Agreed. It looks like his brain had a tiny bit of a very confused moment.

I also love the way Stella is so casual about the fact that the guy who just hit her and got hit in return his her boyfriend.

Well, Stella must have mixed feelings. She enjoys watching Keith finally getting the crap beaten out of him by Tyler, alfter all that he done to her. But at the same time she knows that Keith will keep on coming back again and again. And Tyler's confused too. I mean, he beats up a guy and than he finds out that he's a boyfriend of a girl he just befriended. Talk about an awkward situation.