A Duchess a Day by Charis Michaels

Helena has spent years trying to get out of her marriage to the Duke of Lusk. She finally has an idea that she thinks might finally be the solution. If she finds someone that captures his attention and he cries off, then she will be in the clear. But not too long after arriving in London for the season, she finds herself with a bodyguard. Can she convince the man to help her in her quest?
Declan is a mercenary, but his last job landed him in prison. When he is offered a job in exchange for his freedom, he jumps at the chance. But Helena is not what he expected and he soon finds himself helping her accomplished the opposite of the job he has been hired for. Is he willing to give up his freedom to help the woman he is falling in love with?