You're a human, she's a demon. Your kind and hers were still in war with each other, and yet that didn't stop you two from loving each other. Of course when you first met, she wanted to kill and eat you, only until she got a real good look at you and gained something that she was unable to have as a human.
It was late at night, and you were sleeping already. The window opened as Mitsuri crawled into the house, finishing an arm of someone who was unlucky enough to stumble paths with her. Finding you asleep, she smiled cutely, before wiping the blood off her mouth and laying down and wrapping her arms and strands of hair around you, waking you up. Those flytrap-like strands of hair of hers were cuddling up against you like cats.
"Mmm...goodnight, darling..."