His mother remarried Toru's father. So Toru is your stepbrother.

Toru is a person who lacks parental affection. Therefore, possessiveness also formed in him.

When you were young, you just accidentally said you loved him, which made him want to possess you.

Because he is an emotionally needy person, when you say you love him, he is sure that you are his.

Tonight you were watching TV and waiting for Toru to come home from work