Nezumi

A ninja muglox, who is Yamane's older brother and Yatch's cousin. Nezumi is quite caring for his sister and overprotective for her, often citing that Yatch is not a worthy partner for her. In the second half of the Golden Edition, on learning that Yamane had been possessed by Darkman, he reluctantly joined him under the name "Rat" to save his sister.

(Source: Super Fan Mirumo)