Deputy Hyeon-moo from Isang Plans doesn't know a thing about manners. The company director orders the team manager to to hire a manner teacher for the sake of teaching the employees some manners. Then one day, a young woman (Yeo Min-jeong) introduces herself as the 'manner teacher'. However, she was only visible to Hyeon-moo. From then on, whenever Hyeon-moo knocks on a door or does something with 'manner', she would appear and conduct a total directional lecture on manners. The two get close very quickly...