The Mantis Imagin is a female masochist Imagin with the ability to spray a poisonous purple gas and wield twin rapiers as her weapons. Her goal is to allow a Miku Uehara from the near future to see her grandmother for the last time, as in her timeline she kept putting off celebrating her birthday with her grandmother up until her grandmother died before it could happen. Before the Mantis Imagin can complete her contract and go back in time, New Den-O defeats her.
OOO, Den-O, All Riders: Let's Go Kamen Riders
She appeared to be part of Albinoleo Imagin's group, as in Imagin army, and were part of the this alliance, when the timeline is partially restored and the Riders returns, Mantis Imagin is fighting with Albinoleo Imagin, however she easily defeated by New Den-o.