What's a scene you hate from a series you love?
Here's mine, from the 43rd episode of Yu Yu Hakusho.
All I can think about is how humiliated I would feel if I was in Yusuke's position. I hate it so much, that I have a head-canon where years later Yusuke and Keiko's daughter berates them all for mocking him. Sure, I understand that his friends weren't really being mean-spirited and he knew it. But I also can't help feeling sorry for the guy, because I know that I wouldn't like it if it was me.
I actually see this kind of teasing among friends all the time. Usually I find it funny too, it's just this particular scene that rubbed me the wrong way. Maybe because by this point in the show I had really grown to like Yusuke, so I couldn't help but feel bad for him and empathize.
Plus it's not like with Yusuke whereas his verbal barbs are actually funny; most of it just his so-called friends laughing in his face like a pack of hyenas.