Through Flame and Blade

As an angel trained to fight the forces of demons, Chiara knew to not let them take her alive, but she never expected to survive her first battle. Trapped in the depths of hell and tortured, only one thing is keeping her alive - the demon kept prisoner with her in the cold, dark cell.

As the deadliest demon alive, Logan knew better than to piss off his commander by stealing whiskey and bedding his concubines. But the ladies were lonely and the whiskey was too tempting. He's paid dearly for his transgressions, though, spending months in a cell being tortured, only to regenerate at night for fresh torture the next day. Time blurs and he grows restless to be freed so he can rejoin the battles against angels, until a new captive is brought to his cell. The second he sees Chiara - her beauty and fierce strength, the blinding white of her wings - he is lost and she is the path forward.

He would destroy every demon in hell to free her, but to possess her, he will have to destroy himself.