Tetsuya Watarigani is a blader who first owns Mad Gasher, of which later evolves into Dark Gasher with the help of Doji and the Dark Nebula. He is a strange individual who is unexplainably obsessed with crabs. When he is first introduced, he has a best friend named Echizen, who is later beaten up by Tetsuya. Although he was beaten up, he was not killed, hence the ending of the Metal Fusion, where all who appear in the series are. Tetsuya stood up for Echizen when Taraba, the wandering blader, approached him, wishing to battle. When Echizen ran away in fear, Tetsuya mistakenly took it for betraying him. All in all, Tetsuya Watarigani is a strange guy who loves crabs.