The Wicked Game (2025)

Police officer Than takes a gig guarding Pheem, the youngest son of a private hospital owner. On the hospital's opening day, an assassination attempt is made against Pheem. Fortunately, Than comes to his rescue and—impressed by Than's skills—Pheem asks him to be his personal bodyguard.

Than is an easygoing, straightforward guy. As he gets closer to Pheem, he finds the man to be quite the opposite of him—cold and cunning. When continuous attempts are made on his life and he's exposed to more of the family's cold relationship, he begins to see the hurt and loneliness beneath the cool exterior. Meanwhile, Than's warmth and humour begin to thaw him.

(Source: MyDramaList)