Yutaka Watari (亘理 温,Watari Yutaka?), voiced by Eric Stuart in English, and Toshihiko Seki in Japanese, is 24 years old and a close friend of Tsuzuki's who works for the sixth sector, Henjoucho (which includes Osaka and Kyoto). Nevertheless, he is most often seen in the lab and he is accompanied by Tatsumi when he works in the field. Though technically a mechanical engineer (he has a PhD in engineering), he is basically a scientist who invents whatever comes to mind, most often a sex change potion. He is also in charge of computer maintenance & repair. Though sharing a cheery demeanor similar to Tsuzuki's, whenever something befalls one of his friends he becomes very and suddenly angry.
One of his near-constant companions is an owlet named "003" (001 is a toucan and 002 is a penguin, they stay in Watari's lab). Watari's dream is to create a sex change potion, his self-declared motives being to understand the female mind. He often experimentally tests his creations on both himself and on Tsuzuki, relying on the latter's fondness for sweets to ensure his cooperation. Aside from his apparent familiarity in the laboratory, Watari also has the ability to bring his drawings to life despite the fact that he is a poor artist. According to the author, his hair was bleached blonde by excessive chlorine in a swimming pool.
Late volumes of the manga reveal his past employment with the Five Generals, who were involved in the Mother Project, the supercomputer of Meifu.
Watari stripping Tsuzuki to see if the Devil left his mark.