My Little Monster.

Shizuku Mizutani is apathetic towards her classmates, only caring about her grades. However, her cold view of life begins to change when she meets Haru Yoshida, a violent troublemaker who stopped attending class after getting into a fight early in the school year. He is not much different from her, though—he too understands little about human nature and does not have any friends. Much to Shizuku's surprise, he proclaims that she will be his friend and immediately confesses his feelings towards her upon meeting her.