is a ninja yaoi

Yaoi

In careful Japanese enunciation, all three vowels are pronounced separately, for a three-mora word, . The English equivalent is . also known as Boys' Love, is a Japanese popular term for female-oriented fictional media that focus on homoerotic or homoromantic male relationships, usually created by...

 manga

Manga

Manga is the Japanese word for "comics" and consists of comics and print cartoons . In the West, the term "manga" has been appropriated to refer specifically to comics created in Japan, or by Japanese authors, in the Japanese language and conforming to the style developed in Japan in the late 19th...

 by Temari Matsumoto

Temari Matsumoto

is a Japanese manga artist and illustrator from Nagano Prefecture.She illustrates yaoi light novels and manga. She chose Temari as her pen name since the town she is from, Matsumoto, Nagano Prefecture, is known for making temari....

. The manga was licensed in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 by BLU, the Boys Love branch of TokyoPop

Tokyopop

Tokyopop, styled TOKYOPOP, and formerly known as Mixx, is a distributor, licensor, and publisher of anime, manga, manhwa, and Western manga-style works. The existing German publishing division produces German translations of licensed Japanese properties and original English-language manga, as well...

, in November 2005.

Plot

Another work by Temari Matsumoto, called Cause of My Teacher

Cause of My Teacher

is a Japanese manga anthology written and illustrated by Temari Matsumoto. The manga is licensed in English by Blu Manga, the boys love division of Tokyopop, and was released in September 2009.-Plot:...

 also includes a story about Hiiragi and Asagi.

Reception

Krista Hutley for the Library Journal

Library Journal

Library Journal is a trade publication for librarians. It was founded in 1876 by Melvil Dewey . It reports news about the library world, emphasizing public libraries, and offers feature articles about aspects of professional practice...

 said of Shinobu Kokoro: "Themes of passion and loyalty weave through the three romances, which are sweet if superficial." Tom Rosin for MangaLife noted the explicitness of the manga. Reviewer Julie Rosato disliked how young and compliant the ukes were in the stories, but enjoyed Matsumoto's semes.