Kōtetsu no Hanappashira
Manga
Kōtetsu no Hanappashira is a Japanese manga series written and illustrated by Hiroyuki Nishimori. It was serialized in Shogakukan's shōnen manga magazine Weekly Shōnen Sunday from September 2010 to September 2012, with its chapters collected in nine tankōbon volumes.
Description from Wikipedia, available under CC BY-SA 4.0. May be shortened.