Roppu-Kun

Roppu-kun is a manga series written and drawn by Osamu Tezuka. Its plot runs adjacent to the mainline Astro Boy manga series, and similarly, focuses on the adventures of a robot boy. Roppu-kun was released as monthly serialized chapters from 1963 to 1965.

Story
A human boy named Roppei works as a fisherman with his father. One day, Roppei rescues a robot boy from the bottom of the sea. The robot is re-activated, and introduces himself as the titular Roppu. He was a toy robot that belonged to an alien child, but when the alien child got bored of Roppu, they threw him away. Roppu tumbled into the bottom of the sea, left to be forgotten, until Roppei rescued him.

Roppei and Roppu quickly become best friends. Roppu has a special ability to create almost anything, thanks to the alien technology he was built with. For better or worse, Roppu can generate any gadget or item that Roppei asks him to make. This also makes Roppu a target for criminals who want to use his abilities for evil.

Chapter list

 * 1) A Robot Found in the Sea ( 海でひろったロボット )
 * 2) The Ebigani-like Garbage ( エビガニ式ごみさらい )
 * 3) Some Kind of Dragon Castle ( なんとか城の竜 )
 * 4) The Icicle Demon ( つらら魔人 )
 * 5) The Children Zoo ( 子ども動物園 )
 * 6) Knife Disc ( ナイフ円盤 )
 * 7) Car Kingdom ( 自動車王国 )
 * 8) The Egg Explosive ( たまご爆弾 )
 * 9) Magic Pierrot ( 魔法のピエロ )
 * 10) Phantom of the Helmet ( かぶとの怪人 )
 * 11) Ghost Trunk ( おばけトランク )
 * 12) The Specimen Collection ( 標本集め )
 * 13) The Hypnosis Trumpet ( 催眠ラッパ )
 * 14) Thief Olympics ( どろぼうオリンピック )
 * 15) Spying on Santa Claus ( サンタクロースにばけたスパイ )
 * 16) Dinosaur Country ( 恐竜の国 )
 * 17) Mischievous Wrists ( いたずら手首 )
 * 18) The Snow-Melting Robot ( 雪をとかすロボット )
 * 19) The Mad Bird ( マッド鳥 )
 * 20) I Don't Know My Father ( わからずやのおとうさん )
 * 21) Balloon People ( 風船人 )

Relation to Astro Boy canon
During the final chapter, "Balloon People", several characters from the main Astro Boy timeline as of 1965 can be seen. This officially confirms that the story and events within Roppu-kun takes place adjacent to the Astro Boy canon.

Publication
The Roppu-kun manga was originally serialized in Shogakukan's First Grader and Third Grader magazines. These magazines were released once a month. The Roppu-kun manga chapters were released monthly from October 1963 to September 1965, roughly during the same time the Astro Boy 1963 anime was being broadcast.

The Roppu-kun manga has since been collected in its entirety into two tankoubon volumes. These volumes are commonly available as officially-licensed ebooks.