So... what is actually going on? The dark hair dude disappear on the blond after having se...

So... what is actually going on? The dark hair dude disappear on the blond after having sex once back in high school? Then the blond is now seeking revenge cuz he didnt appreciate (understable) being ghosted? Now we dont know what the dark hair dude is thinking, he is agreeing to sex then in the middle of it changes his mind (it happens).. its confusing cuz the dark hair dude is an enigma to me