the vibe i'm looking for: he's bad for you! he's shadows and manipulation and does whatever he wants. he goads you into the worst version of yourself! he doesn't adhere to boundaries, he just makes a place for himself in your life and you hate it! that unfortunate charm what comes out of the liar's mouth, the way he looks like he wants to eat you alive because you are Light in all the ways he is Dark. he's a burden that hangs itself around your neck and knows it. you don't like him, he's a horrible person and you just accept that. it's easier than pushing him away.
vespers pov: he's everything you fear and you are drawn to it, a moth to the flame. he is light flickering against the oppression of night, the firefly you so desperately wish to put in a jar and keep. he hates you and you love it. he hates you and you wish he didn't but you only make it worse and you do so on purpose. you don't listen, you don't care, you keep showing up at the window of his fire escape. there's no one else who can handle you, no one else who sees you for who you are and despite dislike, doesn't push you away.
he is literally the worst, he's so fucking toxic & to survive him, that probably needs to be met with some indifference. think: an unstoppable force meets an immovable object. maybe they learn how to bend a bit.
bonus points if they have photokinesis / light manipulation to balance vesper's umbrakinesis / darkness manipulation.