His initial attempt with the story ran in Shogakukan's Shōnen Sunday Zōkan from 1985 to 1988, but it was eventually abandoned.

A sequel, titled Birdy the Mighty: Evolution, was serialized in Weekly Big Comic Spirits from 2008 to 2012, with its chapters collected in 13 tankōbon volumes.

In 1996, Birdy the Mighty was adapted into a four-episode original video animation (OVA) directed by Yoshiaki Kawajiri.

Birdy Cephon Altera is a Federation agent chasing interplanetary criminals to the planet Earth.

So, Tsutomu is stuck sharing a body with an attractive, strong, and impulsive space police agent while trying to keep his family and friends from finding out about Birdy.

[12] A sequel, titled Birdy the Mighty: Evolution, was serialized in Weekly Big Comic Spirits from October 11, 2008,[13] to July 23, 2012.

[29] The series was first broadcast on TV Saitama (and later on twelve other terrestrial stations) for thirteen episodes from July 5 to September 27, 2008.

[32] The series was followed by a second season, Birdy the Mighty: Decode 02, which was broadcast for twelve episodes from January 10 to March 28, 2009.

[35] An unaired episode that connects the first and second seasons was included with the special DVD "Birdy the Mighty Decode: The Cipher", released on July 22, 2009.

[42] Bob Muir, from Japanator, noted the ending for the show made it feel rushed, but overall recommended the series, calling it "...just plain fun, with no insipid moe characters or deathly serious world domination plots to drag it down.

"[43] Josh Viel of the Escapist, praised the visuals and soundtrack of the first season, bringing particular mention to the show's use of foreshadowing.