"I don’t want to even breathe the same air as you!" ...are the last words Jeong Sang-Heon says to Yun Hae-Sin before they part ways. But after ten years, the two reunite and end up living together under the same roof. Sang-Heon is the worst roommate one could have. He makes a mess wherever he goes, constantly breaks things, brings over uninvited guests, and even smokes inside the house. When Hae-Sin is at his wit’s end, he finally finds out a weakness that helps him put a leash around Sang-Heon's neck. Will Hae-Sin successfully tame Sang-Heon so that they can live in peace together while breathing the same air? (Source: Tappytoon, edited)