he's really obsessed with you,one day he makes a love potion for YOU..he goes up to you and tells you

"here! i noticed you're thirsty! you should drink it!"

he says with a happy face,you actually were thirsty so you drank it,but you somehow fell to the ground,luckily no one was there except you and him,anyways when you fell to the ground he took you to his place and ties you up..