Yatch (ヤシチ/Yashichi) is a brash and impatient with his henchmen, Sasuke and Hanzo, he continues to annoy Mirmo to no end due to their long-standing rivalry. His favorite dessert is karinto (a traditional Japanese snack food made primarily of flour, yeast, and sugar.). He looks like a ninja Muglox by his apparel and weapons. Yatch is Mirmo's rival. His height is unknown. His physical appearance resembles that of Recca Hanabishi from Flame of Recca. He comes out of the yellow mug. His human partner is Azumi Hidaka, a beautiful student in Katie's school.
Due ninja-like weapons and looks, he might be a ninja-type Muglox. Although unfriendly at times, he helps the others when it's up to him. He was an avid fan of the Warumo Gang and uses a triangle as his magic tool. He's also pretty fond of looking at people's underwear and drawing pictures of them (which he consider precious), much to Azumi's embarrassment. Yatch hates Azumi since she treats him like a slave, but knows that he cannot go on without her.
Yatch also follows Mirmo from the human world, and he became Azumi's Muglox. Azumi was really surprised and tried to hit him anywhere, but Yatch dodges. (He really looks like a ninja.) When he finally stops and introduces, he was hit. But when he tells the proof of being useful, there's a big gust of wind and Yatch was able to see Azumi's underwear. He looks at it and draws it, which makes Azumi very angry. He agrees that he can also try to annoy Katie, Mirmo's human partner.
In episode 65, the Warumo Gang ordered to Yatch to attack the humans. He did it. In the last few minutes of the episode, all the Fairies (Anna, Bike, Mambo/Manbo, Peter/Peta, Gabin, Incho, Enma, Mirmo, Rima, Mulu, Akumi, and the Warumo Gang) were in the rooftop of Katie's school, with the humans (Katie, Dylan, Azumi, Kyle, and Saori). Yatch appears and told to Warumo Gang that he did what they ordered. Mirmo say to Yatch: "I'm disappointed with you, Yatch. I never thought you could attack humans, too." Azumi cries and says to Yatch: "You don't care about me, isn't it?" Akumi uses her magic and pushes Azumi to the wall. Katie, immediately, helps Azumi. Yatch has been very angry with this and allies himself with the good fairies, thus like Sasuke and Hanzo. He has left the Warumo Gang in order to protect his humam partner, Azumi. She was emotioned with what Yatch did for her. Yatch said to the Warumo Gang: "Azumi is my partner and I won't allow you to injure her." The Warumo Gang fires Yatch. With the help of Mirmo, Yatch defeated the Warumo Gang, Akumi and the Fantastic Switcho. This also allows Mirmo and Yatch to be friends.
Azumi uses Yatch for crystal collecting session. He uses his magic to collect crystals. He wishes about thousands of underwear, with a blushing face.
As Koichi Sumita arrives from Katie's school, Azumi uses Yatch's magic to cause trouble for Katie's love, like for getting closer with Koichi.