The Heart Principle (The Kiss Quotient series)

To most, Quan is a surly, underachieving playboy. Anna dislikes him, or so she tells herself. She will never admit that she harbours a secret crush on Quan, especially because he only has eyes for her charismatic younger sister Camilla. Now, with her sister's engagement on the line, Anna must bury her anxieties and overcome her OCD to try and seduce Quan and save her sister's impending marriage.

But when Quan discovers Anna's true intentions, he's forced to confront his own hurtful past and learn to forgive, while Anna must face her greatest challenge: truly opening herself up to love.