Read more about Satsu at: Wikipedia

Official Site: Dark Horse

Satsu is a fictional character created by Joss Whedon for Buffy the Vampire Slayer Season Eight, a comic book continuation of the television series Buffy the Vampire Slayer. Introduced as one of the strongest Slayer, she has a close relationship with her mentor Buffy Summers. Satsu develops romantic feelings for Buffy, and the two have a brief sexual relationship. She becomes the leader of her own Slayer squadron in Tokyo, and forms a friendship with fellow Slayer Kennedy during her performance review. She also makes a minor appearance in Buffy the Vampire Slayer Season Ten.

Whedon and Wolves at the Gate writer Drew Goddard said that Satsu's sexual relationship with Buffy was developed as a way to explore both characters. Her tryst with Buffy drew mixed responses from the media. Several commentators felt that the story arc maintained the show's focus on exploring one's sexuality, and provided insight on Buffy's sexual identity. Others criticized it as a publicity stunt saying it was out of character for Buffy. Feedback to Satsu as a character was also mixed, with the focus placed on the portrayal of her sexuality and race.

Born into a traditional Japanese family, Satsu was pressured by her parents to marry and have children. She faced a backlash from them after coming out as a lesbian. While attending high school, Satsu was activated as a Slayer because of the events of "Chosen" and received all the associated powers. After joining a squad of Slayers based in Scotland, she was recognized as one of the most skilled fighters, and worked closely with her mentor Buffy Summers. Satsu developed romantic feelings for Buffy, which becomes clear after she wakes Buffy from a mystical sleep with a true love's kiss. While taking Satsu on an assignment to destroy a nest of vampire, Buffy reveals that she knew of Satsu's feelings for her; she warns Satsu against pursuing a relationship with her because her past romances have ended in death.

Buffy and Satsu eventually have sex and are discovered in bed by Buffy's friends Willow Rosenberg, Xander Harris, Andrew Wells, and Dawn Summers. Count Dracula steals Buffy's scythe and she recruits Satsu as part of the team to recover it from Tokyo. During the trip to Japan, Willow comforts Satsu and reminds her of Buffy's responsibilities as a general and her heterosexuality. After successfully reclaiming the scythe, Satsu chooses to distance herself from Buffy by remaining in Japan as the leader of the country's Slayer squadron. Buffy and Satsu have sex one last time before they separate.

Satsu has not been a contender in any CBUB matches.