Slasher boyfriend/girlfriend scenarios

Who fell in love first-

Jason Voorhees:
You did! See one day after you had reunited, he picked you a bouquet of wildflowers, and in that moment when he hesitantly handed them to you, saying that he was reminded of how pretty and friendly your eyes were. In that moment, you were oddly crushed and how he only saw you as a friend.

Michael Myers:

He did! He always knew that you were his form of sanity, and the one person he could trust. So he'd always known, and the thoughts if you two finally being together made him keep going.

Leatherface:
He did! When he saw you, he thought you were purdy! And that is not a compliment he'd give just anyone!

Ghostface:
Billy did actually! He was so mesmerized by the way your hair was tied up in a messy bun, or maybe it was the way your eyes sparkled when you were reading, or doing something like draw the crowded hallways of the school. Stu was next, he had seen Billy, despite being in a relationship with Sydney, was constantly flirting with you and nearly threw him into a wood chipper when he wanted to kill you.
After the two had agreed to share you, they killed Tatum, and tried to kill Sydney(which they eventually did), they started to flirt with you, both at once, or one on one.
But you fell fast and hard for both of them. You loved how looney they were together and because you got no positive attention, you loved how genuine compliments they gave you.

Norman Bates:

He did! See he had always felt safe around you so he knew that he loved you. And he just always wanted hold you or be held by you. 

Candyman:

He saw you, he knew you weren't her, but he knew that he loved you. Before he could even blink in your way. Your scent attracted him. He had the need to hold you. To love you. To cherish you.

Yuatja

He chose you as a mate. His species can choose to who they love, but it is mostly involuntary because his body reacts to true mates before he choose to believe he chose you as a mate. He tells you he choose you to be his mate. But that is a lie.

Jeepers Creepers

Your scent made it clear to him that you were his soulmate. So he confronted you. In his own strange way. And you fell for him very shortly after him.