Shoma transforms into Kamen Rider Gavv. He loves snacks very much and works at Hapipare. He is the youngest son of the Stomach family, referred to as 'Red Gavv' by Stomach Corp. He is a half-human, half-Granute.

Hanto Karakida transforms into Kamen Rider Valen. A freelance writer who was modified by Kenzo Suga, enabling him to transform into Kamen Rider Valen.

Lakia Amarga transforms into Kamen Rider Vram. He loves stones. His catchphrase is 'Daru' (what a drag). In the Granute world, he once used a fake name and stayed at Lage 9. He had a younger brother who passed away.

Kenzo Suga transforms into Kamen Rider Bake. The researcher who modified Hanto Karakida and developed Bitter Gavv.

Dark Shoma transforms into Kamen Rider Bitter Gavv. An existence created by Kenzo Suga.

A researcher who developed Vram's belt. Older brother to Shoma and Jeep, and the second son of the Stomach family.

The president of Hapipare and a 'gyaru'. She calls Gavv 'Umasho', Valen 'Hanty', and Vram 'Lakian'.

Older brother to Nielv, Shoma, and Jeep. President of the dark snack company, Stomach Corp. He has an asymmetrical wolf cut with red point mesh highlights. The eldest son of the Stomach family.

Younger brother to Lango and Nielv, and older brother to Shoma. Transforms into Kamen Rider Bitter Gavv Bakibaki Stick. He has no connection to the other Dark Shoma Bitter Gavvs. Husband to Lisel Jardack and very kind to her. The third son of the Stomach family.

Jeep's wife. An inquisitive only daughter of a wealthy family. She wears a blue dress, has silver hair, and carries a blue umbrella.