Meijin seems to be an expert on net navis, seeing as he was the one who created Heatman. Wearing a big white labcoat and sporting some nice eyewear, this somewhat of a nerd has the ability of creating some of the most powerful navis ever. After the conclusion of Season 2, Meijin joins Netto's father Yuuichirou Hikari at the Science Labs, where they work together. Meijin has a couple of really fun and neat quirks about him. First off, he refuses to have -san attached to the end of his name, and Netto constantly forgets that. Thus, everytime we hear "Meijin-san!" out of Netto, Meijin always responds with "-san wa iranai!" ("no need for -san!"). You might see that the fansubs translated it as "Formalities not needed!", which makes perfect sense too. The -san is a form of respect for someone older than you. In Meijin's case, he doesn't want to seem "old". We learn in Axess that Meijin is also a profound and dedicated collector of little toys. In this case, we see a collection of mini cars. It's rather amusing to see Meijin foaming at the mouth right next to Netto at a new batch of mysterious new toys in a box at the store. Lastly, we learned in Beast that Meijin does in fact have a "significant other"....or at least he used to. He's quite friendly with his ex-girlfriend Makoto Aoni, and as the series progresses they end up working together more often. These two science geeks seem to be rather perfect for each other. Meijin's name is a pun off of the -real- Meijin, who is a game story developer for the EXE series. "Meijin" (which means "Master" or "Expert" in Japanese) is only his nickname, his real name is Masakazu Eguchi. Anyways, you will frequently see the "real" Meijin dressed up in the current attire of the "character" Meijin at Japanese EXE events.
