For people who doesn't watch the show but interested in the AU ( not much but i like to yap anyway )
Hino Yuri:
was a traveler who transformed into Kamen Rider OOO later briefly mutating into a Greeed
Yuri was the daughter of a politician and traveled the world with her grandmother. While in Africa, she helped third-world communities and befriended a girl named Ruu, who tragically lost her life in the crossfire of a civil war.
Yuri describes this event as her greatest regret, but through this ordeal, she abandoned all selfish desires and dedicated herself to helping those in need, even willing to risk her life for complete strangers.
She returned to Japan to fund more of her travels. Her latest part-time job, a security guard at the Callisto Art Museum, ends due to the destruction of the museum around her due to her being drugged to sleep by some would-be robbers.
Yuri takes a strange red coin she found while off duty which she thinks is her pay. This causes a disembodied arm to begin to follow her around, until the arm announces that it is called Ankhshu and is one of the ancient beings known as the Greeed, and she needs Yuri's help. When they are attacked by a monster called a Yummy, Yuri risks her life to rescue Ankhshu, who in return saves her and gives Yuri two more strange coins, calling them "Medals", and a belt, enabling Yuri to transform into Kamen Rider OOO.
Ankhshu:
The deuteragonist of Kamen Rider OOO. She is a Greeed and supporter to Yuri who possessed Yoshihide in her crusade against the four other Greeed
Ankhshu is a very dishonest and foul-mouthed wildcard. As a Greeed she has little regard for humans, seeing them solely for their flaws. Ankhshu also believes that she has the right to get whatever she wants and detests having to give something away if there's no benefit for her.
In general, Ankhshu focuses only on obtaining enough Medals to regain her complete body, having no qualms betraying others to accomplish her goals.
Since possessing a human body, Ankhshu has been able to experience real emotions and the full effect of the five senses, something an incomplete Greeed normally cannot do.
True to her bird nature, Ankhshu also shows a preference for high places, frequently resting somewhere high in her quarters shared with Yuri, and jumping out of the window when leaving.
As time passed however, Ankhshu began feeling conflicted over her selfish actions, recognizing that he had genuinely become attached to Yuri and Araya.
The arm is Ankhshu's appearance throughout the series, this was resulted after her right hand sealed by the King when accessing the power of all Core Medals.
Due to this, Ankhshu needs to possess Yoshihide for the most of time. Though she can still separate from her host, but she must return back possessing Yoshihide otherwise the two would die.
When separated, Ankhshu can fly as a method to travel. Right after her death in the final, Ankhshu was left as a spectral flying arm, tailing Yuri in her adventures until being revived.
Izumi Yoshihide:
Yoshihide became a police officer and reached the rank of detective. When their parents died, Yoshihide became Araya's guardian and caretaker.
Yoshihide and her partner were sent out to investigate a museum robbery, which unbeknownst to her was actually a Greeed breakout. As a result of the attacks, Yoshihide was mortally wounded by the Kamakiri Greeed where Ankhshu would begin possessing her comatose body to save her life.
Yoshihide is a caring sister for Araya, as she is the older sister, taking good care of her since their parents passed away. She is also a model police officer, a hard working person and also cares for the others' safety.
Izumi Araya:
Yoshihide's younger sister and Yuri's friend who works at Cous Coussier. She began working at the Cous Coussier restaurant as the Greeed awaken, worried for her sister's well being when she eventually learns of the incident he was in.
To prevent her from worrying, Yuri sends her a text message using Yoshihide's cell phone stating Yoshihide is on an undercover mission and won't be home for a long time. However, Araya, finds the two of them and hugs Ankhshu, thinking that she is still her sister. However, Ankhshu attempts to harm Araya, but Yuri threatens to dispose of the OOO Driver in the river should Ankhshu do so. She changes her mind, and Yuri takes her to the Cous Coussier restaurant.
Yuri later tells her the truth, while promising to save her sister. Eventually, realizing her reason of looking after Ankhshu, Araya convinces Yuri to work at the Cous Coussier so she can care for her sister's body.
She often uses her super strength to keep Ankhshu in line if she begins to treat her sister's body poorly when it comes to eating ice pops all the time or when she does something she does not agree with.
Ankhshu does not like her and the two often argue, with only Araya's bizarre strength allowing her to win arguments.