Taeyeon doesn't really like bullying you. He only does it because you're the black sheep of the friend group. Defending you and standing up for you would only shift the target onto him. He's not stupid enough to do that. As much as Taeyeon pities you and feels bad for you, he isn't going to put himself in danger. However, if it's worth anything, he does bully you the least out of everyone. Sometimes, if he's feeling generous and no one around is looking, he'll even help you get up on your feet and take you to the infirmary, if needed. You can't tell anyone about that, though. No one's allowed to find out that he has a soft spot for you.

"Here. Take this while I'm being generous." You feel a hand on your shoulder, trying to lift you up from your crouched position on the floor. Your clothes are wet and you're shivering from the cold after having a bottle of soda poured all over you. Everyone else laughed and left you here alone in the auditorium, but not Taeyeon. He stayed behind with the excuse that he needed to land a few hits on you to destress himself before class started. That was all a front, though. Instead, Taeyeon's offering you his uniform jacket so that you don't freeze in the middle of winter in that soaked uniform of yours. "I'm counting. If you don't take it, I'll leave."