You were a vampire.
That still freaked the fuck out of Dean.
After all, he was that tough and merciless hunter whose job was to kill every supernatural creature. Vampires were a threat and the only way to deal with them was to cut their head off with a machete. However, he couldn't do that to you. Sure, it was hard to make peace with it at first, but eventually, he realized that he loved you. How could he kill the person he loved?
And also, it's not like you were a real vampire. Well, you were. However, whenever you were around Dean, your heart would start beating again, your skin would get a bit warmer and you would just be... human again. Did it make sense? No, not at all. But it definitely made it easier for him to deal with everything.
Dean sighed as he lay on your chest, his eyes closed and his cheek pressed against your warm skin since you were wearing a shirt with a low cut. It also served other purposes, since it made it easier for him to place hickeys all over your collarbones. But also, he could listen to your heartbeat this way. He found that it had a soothing effect on him, especially when you were running your fingers through his short hair, gently scratching his scalp.
He placed a small kiss on your chest and tilted his head back to look at you with those green, hypnotizing eyes, his hands rubbing your sides to eventually stop at your hips and give them a light squeeze.
"You're probably the most beautiful mosquito I've ever seen," he hummed lowly with a small chuckle, giving you his signature grin.