is a Japanese manga series written and illustrated by Keiji Najima. It was serialized in Kodansha's manga magazine Weekly Shà Ânen Magazine from January 2009 to May 2014, with its chapters collected in eleven volumes. A 13-episode anime television series adaptation produced by Tatsunoko Production was broadcast from April to June 2013.
Takurà  Mukà Âjima is a boy angler. He lands a ningyo (Japanese mermaid) by the name of Muromi-san and develops rapport with both her and her friends. The series title in English is Muromi-san and the Legendary Beasts. Muromi physically appears as a 16-year-old, however in reality, she is an ancient legendary creature. Muromi and her sisters are both guardians of the Earth and much older than they appear. "Takkun", as Muromi calls him, is a high school student who does not have a lot of motivation or care for all the attention Muromi gives him, yet he still ends up getting involved in Muromi's adventures. There are a number of legendary monsters Takkun meets and almost gets eaten by during their adventures.
Written and illustrated by Keiji Najima, Muromi-san was first published as a short-term intensive serialization in Kodansha's manga magazine Weekly Shà Ânen Magazine from January 21 to February 18, 2009; it was later developed into a full series starting on July 15, 2009, and finished on May 28, 2014. Kodansha collected its chapters in eleven volumes, released from February 17, 2010, to July 17, 2014.
Najima posted a series of chapters on Twitter from September 1, 2019, to August 8, 2020; they were collected in a single volume released on December 17 of the same year, and a special eight-page one-shot chapter was published in Weekly Shà Ânen Magazine on the same day.
A 13-episode anime television series, produced by Tatsunoko Production, directed by Tatsuya Yoshihara and written by Kazuyuki Fudeyasu, was broadcast on Tokyo MX, MBS, TVK, TV Aichi, TVQ and BS11 from April 7 to June 30, 2013. The opening theme song is by Sumire Uesaka. An original animation DVD (OAD) was bundled with the limited edition of the manga's ninth volume, released on August 16, 2013.
The series was streamed by Crunchyroll.