The male protagonist He Yu'an witnessed his father being killed by a demon in front of his eyes when he was a child. Under the guidance of his father's master, He Yu'an also grew up to be an outstanding demon slayer, but he never understood the look in his father's eyes before he died. After experiencing a series of events with the companions he met, He Yuan finally discovered that people with seven emotions and six desires are no different from monsters, and also understood the meaning of his father's final look...
