Zodiac P.I. is a mystery manga series written and illustrated by Natsumi Ando. Appearing as a serial in the monthly shōjo manga magazine Nakayoshi from the April 2001 issue to the January 2003 issue, the chapters were compiled into four bound volumes by Kodansha and published from November 2001 to March 2003. Set in present-day Japan, the series focuses on Lili Hoshizawa, a teenage detective who uses astrology to solve cases.
In North America, Tokyopop licensed the series for an English-language translation, and published it from July 2003 to December 2003, although the translation has since gone out of print. The series has also been translated into other languages. The series has been generally reviewed as being light entertainment.
Set in modern-day Japan, the series centers on 13-year-old extrovert Lili Hoshizawa, who uses astrology to solve crimes, and manages her missing mother’s fortune-telling business on the side. Her childhood friend, Hiromi Oikawa, assists her, after he returns from the United States, where he studied criminal psychology. As Detective Spica, Lili uses the magical star ring, left to her by her missing mother, to aid her in solving crimes by consulting with one of the twelve astral spirits in the ring and learning the victim’s horoscope. Her father, Inspector Hoshizawa, disapproves of her actions. Periodically, she encounters rival private investigator Sirius, who tests her mystery-solving skills.
While solving cases, Lili eventually learns from Hiromi’s elder sister, Megumi Oikawa, that Hiromi’s allergy to girls resulted from her: ten years ago, he waited in the rain for Lili to show after he left her a love letter. Lili encounters Zeus, a fortuneteller and hypnotist who kidnaps her father. After Hiromi rescues him, Zeus takes Hiromi captive and demands the star ring in exchange. Realizing that Sirius is her missing mother, Lili frees her from Zeus’s hypnosis. Lili learns that her mother disappeared to protect her family from Zeus, who hates Sirius, as he believes that she kidnapped his girlfriend and caused her to become comatose. Lili uncovers the truth: his girlfriend feared that he desired the star ring more than her love and asked Sirius to stage a kidnapping and have him decide between her or the star ring. When he hesitated, she was devastated and threw herself off the cliff. After learning this, Zeus loses his desire for the star ring and lets Lili, Hiromi, and Lili’s mother leave. Lili accepts Hiromi’s love for her. In the conclusion, Lili’s mother takes over her fortune-telling business, and Lili continues to solve crimes with Hiromi’s assistance.
Manga artist Natsumi Ando enjoyed astrology in her childhood and had a fondness for stars and Greek mythology. For File 2, which deals with a mystery in a piano school, Ando researched a local music school. The design for the Libra astral spirit originated from the winner of the Astral Spirit Design Contest; many of the design submissions were for the Libra, Pisces, and Cancer spirits.
Ando included references to Greek mythology in Zodiac P.I. in the names of the astral spirits. The astral spirit of Virgo, Demeter, takes her name from the goddess of the harvest, while the astral spirit for Capricorn, Parn, is a reference to the god Pan. Astrea, the astral spirit for Libra, is named after the goddess of justice. The twin astral spirits for Gemini take their names from twin brothers Castor and Pollux. The centaur Chiron is alluded to in the name of the astral spirit for Sagittarius. The name of astral spirit for Taurus is a reference to the woman Io. The astral spirit for Pisces and the spirit for Aquarius take their names from the goddess of love and Ganymede, respectively. Other references include stars. Ando named Antares, the astral spirit of Scorpio, and Regulus, the astral spirit of Leo, after the Antares and Regulus stars, respectively.
Written and illustrated by Natsumi Ando, Zodiac P.I. appeared as a serial in the monthly manga magazine Nakayoshi from the April 2001 issue to the January 2003 issue. It published the series in four bound volumes from November 6, 2001, to March 4, 2003.
In North America, Tokyopop licensed the series for an English-language translation. It published the series from July 8, 2003, to December 9, 2003; the translation has since gone out of print. Zodiac P.I. has also been translated into other languages, such as Finnish, German, and Italian.