Grinsha is a white Overlord Inves and a minor antagonist in Kamen Rider Gaim.
He was voiced by Yuki Anai.
Grinsha was assigned by Rosyuo to assist Redyue in her invasion of the Earth. He was ordered by Redyue to capture civilians for them to sacrifice. Grinsha soon came across Akira Kazuraba and the survivors are hiding.
Grinsha later fought against Kamen Riders Gaim Kiwami Arms and Baron Lemon Energy Arms. The two overpowered Grinsha, but he was saved by Redyue before they could destroy him. Grinsha would later fight the two Riders again, only to be defeated and destroyed by them.