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Also known as Birdy the Mighty, it is a manga series by Yuuki Masami initially made from 1985 to 1988. A reboot was produced that ran from 2002 until 2008. A four-episode OAV was also made in 1996, followed by a 25-episode anime from July 2008 to March 2009.
Birdy Cephon Altera is a Federation agent chasing interplanetary criminals to the planet Earth. While in pursuit of one such criminal, she accidentally kills a high school boy named Senkawa Tsutomu. However, there is a way to keep him alive. He ends up being merged into Birdy's body and must remain so until the repair of his body is complete. 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. In the meantime, Birdy continues her investigation. Together, they take on a secretive group of evil aliens planning to perform experiments on the unsuspecting inhabitants of Earth.
The following tags are aliased to this tag: birdy_the_mighty (learn more).