Yuriko Misaki was a newly finished cyborg ready to serve the evil Black Satan organization but she was still inactive. Everything changed as her soon to be best friend Shigeru Jo entered the room she was staying in trying to find a way out of Black Satan`s secret lair finding her on an operation table and awakens her. After some talk he convinced her to come with him and together with a good friend to many Kamen Riders, Tōbei Tachibana they fought the Black Satan as Kamen Rider Stronger and the Electro-Wave Human Tackle for quite some time. Over time she fell in love with him. But sadly Yuriko gave her life to defeat the evil Doctor Kate in order to save Shigeru from being poisoned. This would forever haunt him and pushed him to go under surgery in order attain the even more powerful (and dangerous) Charge Up form.