Michiko Shibata is single, unattached and unemployed after her previous employer went bankrupt. Failing to land a job, she leads a destitute life surviving mainly on cabbage but craving meat. And she has tapped out financially after lending all of her savings to a handsome young man she pines after.
Her life reaches an all-time low when she reaches for a can of cat food found on the street, but just then, former supervisor, Kurosawa appears and wonders what she’s doing. ”I’m dying for meat,” she wines. So Kurosawa takes her to a coffee shop he runs called “Himawari” (Sunflower) and offers her a part-time job. Michiko hesitates as she remembers the nightmarish life working under this tyrannical man at the last company. But at Himawari, he seems to show a different side. Maybe the fortunes of this sorry woman is about to change.

Tokage (lizard) is an ex-cop from the Metropolitan Police Department's 1st Crime Division who couldn't work well with people, and never opened up to anybody. But he had extraordinary abilities that included a photographic memory and unmatched physical skills enabling him to crack the most difficult cases. For this, he had the respect of his peers and bosses. Until one case that led to a fatal miss: the death of his only partner. Taking responsibility for the tragedy, Tokage quit the force and began working for a private investigator's office as a researcher. But the Metropolitan Police are eager to recruit him back in an effort to raise their arrest rate, and manage to convince him to return as an undercover cop. Assigned to assist him is a young woman from the detective agency who joined for certain unavoidable reasons. But she's not in the least meticulous and smacks of a rich girl upbringing, and yet is obstinately strong-willed and doesn't back down. Together, they form an odd pair - the eccentric big name cop and the tough but cute assistant in an absolutely new kind of detective story.

“Mommy will be back in the rainy season.” Mio Aio wrote these words in a picture book just before passing away. Though six-year old Yuji accepts his mother’s death, he still believes the promise his mother made. Then the rainy season comes, and Yuji and his father, Takumi, meet a woman in the downpour that bears an uncanny resemblance to Mio, but has no recollection of who she is. Taking her in, they reacquaint her with her former self and family life returns to normal as memories come flooding back. But their new life together is interrupted by the discovery of Mio’s old diary, which reveals the secrets of her past and how they must say goodbye in six weeks time….