Akiyama Tohru (秋山透)

Tohru was the original founder and leader of GEO. One month before Haru was hired at GEO, Tohru stole GEO’s prototype FieldSlider and disappeared without a trace. She now fights as Kamen Rider Obsidian, frequently clashing with Haru.

Tohru is a serious and anxious person. She hates the Regoliths but fights for them because she is being blackmailed - they have her best friend hostage in a near-death state, and promise to release him alive if she can kill Crystal.