Sigma Sin Series by Eva Simmons

From the moment I spotted him on the side of the road, I knew he was trouble. Now I'm kneeling at the mercy of a masked devil with my boyfriend's blood on my hands. He tells me to call him Saint because he saved me. .. that I should be thankful he spared me a worse fate. I'm tempted to fight him or bargain. But when Saint tells me to run, a twisted part of me wonders if he'll chase.

I made a deal with the devil. .. Declan Pierce is a bully and a sadist. He’s been my enemy since birth, and he’s made my life a living hell. But when my father barters me in an arranged marriage, Declan proposes a deal I can’t refuse. After all, so long as Declan owns my soul, it can’t be sold to another…. But it turns out Declan wants more than I bargained for. My body, my submission, the truth behind what sent me to Montgomery Psychiatric Ward three years ago... moreI made a deal with the devil. .. Declan Pierce is a bully and a sadist. He’s been my enemy since birth, and he’s made my life a living hell. But when my father barters me in an arranged marriage, Declan proposes a deal I can’t refuse. After all, so long as Declan owns my soul, it can’t be sold to another…. But it turns out Declan wants more than I bargained for. My body, my submission, the truth behind what sent me to Montgomery Psychiatric Ward three years ago. And he’ll haunt every facet of my existence until he gets it. I thought death was the only truly inescapable thing. After all, nothing is eternal… except maybe him. Author's Note: Eternal is an extremely dark college romance with a morally irredeemable MMC, heavy subject matter, mature content, and explicit scenes. Content/TWs (which contain spoilers) can be found on author's website. 18+ only. less

Alex Lancaster is a gorgeous monster. A vicious legend. A story his fraternity tells to scare away the weak. And I’m his obsession…. While everyone thinks Alex has been locked behind the walls of Montgomery Psychiatric Ward for the past two years, he’s been secretly watching from the shadows. Waiting. Manipulating my life and sabotaging my relationships. I try to tell myself it’s because he understands me. The same fraternity that nearly killed him is responsible for my best friend’s death... moreAlex Lancaster is a gorgeous monster. A vicious legend. A story his fraternity tells to scare away the weak. And I’m his obsession…. While everyone thinks Alex has been locked behind the walls of Montgomery Psychiatric Ward for the past two years, he’s been secretly watching from the shadows. Waiting. Manipulating my life and sabotaging my relationships. I try to tell myself it’s because he understands me. The same fraternity that nearly killed him is responsible for my best friend’s death. Our trauma goes hand in hand. Unfortunately, so do our lies. Alex is no prince. No savior. No god. And the truth is, I’m no better. There’s only one way to rise from the ashes, and that’s to burn. We might as well both go down together. This series contains overlapping timelines and plot points. It is highly recommended to read Saint and Eternal first. Author's Note: Atone is an extremely dark romance with a morally irredeemable MMC, heavy subject matter, mature content, and explicit scenes. Content/TWs (which contain spoilers) can be found on author's website. 18+ only. less

I didn’t know Jacob Gray was my professor when I fell into his lap on the plane. All it took was a devastatingly gorgeous man twice my age to break all my rules. To teach me how to let go. How to surrender. How to submit. But then I learn Jacob isn’t who I think he is. And it turns out us meeting wasn’t an accident. The sweeter the forbidden fruit, the more venomous the snake. Jacob wants revenge, and he’s going to use me to get it... moreI didn’t know Jacob Gray was my professor when I fell into his lap on the plane. All it took was a devastatingly gorgeous man twice my age to break all my rules. To teach me how to let go. How to surrender. How to submit. But then I learn Jacob isn’t who I think he is. And it turns out us meeting wasn’t an accident. The sweeter the forbidden fruit, the more venomous the snake. Jacob wants revenge, and he’s going to use me to get it. Author's Note: Revere is an extremely dark professor romance with a morally irredeemable MMC, heavy subject matter, mature content, and explicit scenes. Content/TWs (which contain spoilers) can be found on author's website. 18+ only. less