"He was poison to my life. He could easily ruin my relationship with my parents. He didn't want to or mean to. I could just tell him he's bad for me and move on with my life, but that was the problem. I didn't want to."
The one where Michael never wanted Calum to find out his deepest darkest secrets.
Or Michael doesn't think he's good enough for Calum so he represses his feelings and fucks whoever's willing.