OVA bundled with the 10th volume of the One Punch Man manga. It features an original story by the series' mangaka, ONE, about the secret story of the birth of Saitama's hero suit.
Description (Spoil Text):OVA bundled with the 10th volume of the One Punch Man manga. It features an original story by the series' mangaka, ONE, about the secret story of the birth of Saitama's hero suit.
