Tatsumi Hōjyō is a 17 year old dreamcatcher (yumegari) from the Houjyo clan who has to investigate the dreams of others and sometimes participate in them. A yumegari is bound by fate to a yumemori, one who watches the dreams of a Yumegari and prevents them from falling into an eternal sleep.

When Tatsumi's mother and father, the preceding yumegari and yumemori, die in the execution of their duties, Tatsumi inherits the job. At the risk of being caught in the dreams, as happened with her parents, the yumegari Tatsumi is helped by a dreamseer (yumemori), called Kyosuke Kaga, a 28 year old novelist with whom she'll have to share a new life in Tokyo to try to understand more about her extraordinary powers and control them. However, their relation becomes more personal, despite the warnings of the Houjyo clan about the yumemori.