Lives in the Mizuki household. Transforms into Kamen Rider Mice. Transformation items: Ride Ex 01 and Mice Driver. Male. Changes forms into Wolf Form, Turtle Form, Hawk Form, and others. The user's name is Sora Otozumi.

Leader of the Zodiac Alliance. Male. Kind personality with great charisma. Represented by the Cat.

Transforms into Kamen Rider Mutton. Uses Ride Ex 08, the Mice Driver, and the Bite Bone Buckle. Female. Always sleeping. Does things at her own pace.

Transforms into Kamen Rider Dat. Female. Transformation items: Ride Ex 04, Splash Bone Buckle, and Mice Driver.

Transforms into Kamen Rider Jao. Uses the Bite Bone Buckle, Ride Ex 08, and the Mice Driver.

Transforms into Kamen Rider Vanken. Male. Uses Ride Ex 11, the Shot Bone Buckle, and the Mice Driver. Enjoys haiku.

Transforms into Kamen Rider Diggle. Male. Uses Ride Ex 03, the Scrash Bone Buckle, and the Mice Driver.

The young lady of the Mizuki family. She grants permission for Sora to transform and cancel his transformation. Her command for transformation is "Become a little mouse!" and for canceling it is "Back to human!" Female. Innocent and kind personality. Hates studying. Loves looking into mysterious incidents.

A member of the Zodiac Alliance. Transforms into Kamen Rider Ende. Transformation items: Ride Ex 09, Mice Driver, Saru Arrow, and Scrash Eight Bone Buckle. Male. Kind personality, sworn loyalty to Lord Maou.