Armed with a metal sash that straightens into a sword, lanky swordsman Van is traveling through the desert, searching for the mysterious clawed man who killed his bride. Along the way he picks up a fellow traveler: Wendy, a young girl whose town he saves from bandits by summoning a mecha with his sword. Wendy is searching for her missing older brother, whose engraved gun she carries on her back. In their mutual quest they run afoul of more bandits and villains, a mysterious woman named Carmen99, and more mecha battles a la Wild West.

[Source: Anime News Network]

These are a series of 13 omake episodes of Gun x Sword, tied in very loosely to the plot, with the characters as chibi puppets. The main characters are Wendy and her turtle, Kameo, who is the size of a human in this series and is able to talk. All the episodes seem to center around analyzing various events in Gun x Sword and mocking the themes displayed.

They are included on the DVDs.

[Source: Wikipedia]