There Are No Saints by Sophie Lark (Sinners duet #1)

She knows he's no saint, but she has no idea she's dancing with the devil.
Cole Blackwell values control. He's the hottest sculptor in San Francisco - wealthy, successful, and respected. His only weakness is the dark impulse he carefully conceals. In truth, he's not just an artist: he's a predator, and the city is his hunting ground.
Mara Eldritch is a nobody. Broke and damaged, she works three jobs while creating paintings no one will ever see. When a chance encounter throws Mara into Cole's path, her escape from certain death fascinates Cole. More than that - it fixates him.
He begins stalking her, discovering there's more to the struggling misfit than he would have guessed. She makes him feel things he never thought he could feel. Want things he thought he'd never want. He doesn't know if he should protect her at all costs or destroy her before she ruins him. He's losing control, breakingthe rules that have kept his true nature hidden from the world.
Mara knows he's dangerous, but Cole is the only person who's ever recognized her talent, and it leads her heart astray, straight into the dark.
Cole can teach her to get what she wants. . . but what might this vicious killer want in return?
Content warnings: serial killers, blood, dubious consent, graphic murder, graphic violence, mentions of child abuse, kidnapping,stalking, emotional abuse, self harm, sexual assault, alcoholism, torture.