My Bodyguard Is an Assassin

The world's number one assassin, Cole, retires and comes to Dragonport City to become a humble security guard in a bar. By a twist of fate, he has an encounter with the beautiful CEO, Rosalind Lynch, and is subsequently brought home by her to be a personal bodyguard, responsible for protecting Rosalind and her two sisters. The four of them fight against evil forces together, ultimately achieving a great victory. From then on, they begin a happy and blissful life.