Oh My Ladylord

Oh Joo In, a top rom-com actress, has been aiming to repurchase her old family home. The second it goes on sale, she buys it back, but it turns out that Han Bi Soo, an award-winning crime-thriller scriptwriter who has turned Joo In down for several roles, has been living there. As a man of many neuroses; disinfecting his surroundings and making sure everything is at a perfect angle, Han Bi Soo is so used to writing in his designated writing room that he can't seem to write anywhere else. So he enters into a contract with Joo In, to be allowed to use that room 24/7, on the condition that he calls her master. (Source: kortkrachtig at MyDramaList)