Takeda Kouji

The balance of the Creature World is starting to crumble. A talking deck case named Decky comes to the human world to search for a Duel Master to preserve equilibrium. There he sees Joe's power to create creatures. Source: ANN

* Based on an adventure historical seinen manga series by Hara Yasuhisa.

The story centers around an elementary school teacher who is so stupid that he cannot even write his own name. He does whatever he likes in his classroom. Plus, by all appearances, he is not human. Source: ANN