A young man moves into a run-down apartment building and soon gets into a relationship with a neighbor. Both the characters and the building have traumatic histories, and over time the ghosts of their past come to light.

In 2028, cartoonist Han Cho becomes obsessed with his neighbor, an assassin named Nana. He professes his love for her but she remains indifferent. By accident Han Cho finds an amnesia-inducing drug which he uses to spike Nana’s drink. With her memory blanked out, Nana is told that she is Han Cho’s girlfriend.