Why can’t I dislike him?

Ever since I joined year 12, there is a guy whom, along with his group of friends, laughs at and/or makes faces whenever I ask a question in one particular class. I reported him and the issue is mostly sorted now. But I can’t dislike him. He was nice to me in the odd times (before I reported him) like saying “sorry” or “thank you”. We also participate in the same after school club where we sometimes communicate and he’s polite. But I think this isn’t the only reason I don’t dislike him. I can feel that underneath the meanness, he’s a nice person. I felt it even before I realised what he was doing to me behind my back. Why this feeling?
1) Is my intuition right and he’s genuinely a misguided kind person that’s doing this for popularity from this friends?
2) I like that I can SENSE kindness from him even though he’s not kind, which makes me give him more credit than he deserves thus makes me not able to dislike him?
3) Alternatively, context to add, his aura is strangely the same as my little brother. I can’t explain it, but he gives little brother vibes…I won’t delve further upon it because I really can’t explain it. Maybe I can’t dislike him because he reminds me of my brother?

I’m asking this, because I have anger issues and high morals, so if anyone did what he’s doing to me, an innocent person, I would dislike the person. Strangely, I don’t, and I even feel pity for him (or 5), is it empathy because I know he might be doing this for popularity?)

No rude replies please! Seeking for my self-awareness