Riko Sakurauchi

"'Calm As The Swan, AquaWhite!'""-roll call""'With The Calmness Of The Swan, Super AquaWhite!'""-second roll call"Riko Sakurauchi (桜内梨子) is AquaWhite of the Aqours Rangers.

Personality
Riko is modest, refined and polite, however, while trying to remain calm at times, she panics when the situation gets too tense. Chika states that Riko is scary when angry, which is odd for her as she is calm most of the time. Riko shows hatred towards Demon Hound for killing her best friend and 'senpai', Miku Yuzuki, which she blames herself for, especially for her fear of dogs, which gradually goes away. She has a crush on Chika, who is very protective of her.

Past
Riko was born in Tokyo to musician parents. When her father died, Riko decided to take piano lessons as a tribute to him. She began her high school years at Otonokizaka Girls Academy, the same school where the Muse Rangers went. She was outcasted by her classmates because she spent most of her time in the music room except for her 'senpai' Miku Suzuki. Despite being annoyed by her, Riko sees her as an older sister.

On her way home after piano lessons, Riko gets attacked by Demon Hound and his gang of Demon Knights. She nearly gets killed until Miku saved her. Riko watched in horror as Demon Hound kills her senpai, causing her to become afraid of dogs. Miku dies on Riko's arms, telling her not to let her 'fear become hate as it will lead to nothing'. Miku's death made Riko vow to avenge her.

Ranger Life
Sometime before starting her second-year of high school at Otonokizaka Girls Academy, Riko and her mother moved to Numazu. There, Riko saw a hooded woman heading into the forest and demon following her. As she head there, the demon, Demon Devil, attacks the hooded woman and Riko quickly defends her and gets saved by local, Chika Takami. The hooded woman gives Riko her Aqours Animal Transformation Brace and Animal Cell #2, becoming AquaWhite, wielding the powers of the swan. After defeating Demon Devil, Riko and Chika hang out at the beach. Riko tells Chika that she's from Otonokizaka Girls Academy and has never heard of the Muse Rangers, shocking the latter. She seems impressed by Chika's aim to become a zoologist like her parents but comments it as impossible.

Riko enrolled into Uranohoushi Girls High School. She is shocked to learn that she is in the same class as Chika and her best friend, You Watanabe. She gets annoyed with Chika trying to reveal their identities. Later on, Riko transforms into AquaWhite and with AquaOrange and AquaBlue, they defeated Demon Devil. Riko developed a strong bond with her partner, Aqours Swan.

Riko developed a close relationship with Dia Kurosawa/AquaRed. In Loneliness Can Never Take Over Me!, Riko noticed Dia suddenly feeling left out of team. Later, when the latter trains to defeat Demon Samurai, Riko convinces Dia that her loneliness can never take over her, no matter what others say. After Demon Samurai's defeat, Riko comments that Dia has finally warmed up to them after the latter gave the team cupcakes, which she (Dia) gets embarrssed.

AquaWhite becomes Super AquaWhite with her team in episode 26.

In The Hound Of Tokyo!, Riko encounters Demon Hound and attempts to fight him on her own but almost gets killed, especially for her fear of dogs. Yoshiko notices this and helps her get over her fear of dogs. Riko tells her underclassman that she wanted to kill Demon Hound for killing her senpai back in her time at Otonokizaka Girls Academy and claims she hates him. Yoshiko tells her that her hate will lead to nothing, reminding Riko of the same thing that Miku told her. Demon Hound reappears before the two and attacks them. Super AquaWhite is almost on the verge of defeat until she remembers Miku's words prior to her death: that her fear can be conquered through the encouragement of her friends. With that, Super AquaWhite gets given Animal Cell #23 by Super AquaBlack, wearing the Armadillo Armour, and defeats Demon Hound and once again with Doubustu Gattai Aqours: *2*6*8.

In the final battle, after Aqours Swan and Aqours Lion got captured, Riko joins Chika to save her. While in the palace, Riko remembers the time when they first met and confess to her leader that she loves upon first meeting. After saving their Aqours Animal Partners, Riko feels weak after fighting against a revived Demon Hound once more. Chika, who wants to protect, quickly her pushes out of the palace and gets saved by Aqours Swan. Riko then joins the rest of her teammates, telling them the danger Chika has put herself in. She then witness the Akuma Palace explode in horror as she cries out for Chika.

After the graduation ceremony and funeral service for Chika, Riko remained depressed and silent about Chika's death as her teammates try to comfort her. Chika suddenly appears from the sky, alive and carried by the Aqours Animals. Chika apologized to Riko for making her worry and decides to make it up to her by making sandwiches for her. A tearful Riko hugs Chika, calling her an 'idiot'.

Doubutsu Sentai Aqours Ranger Returns: Revenge Of The Demons
Months after the final battle, Riko succeeds Dia as Student Council President and misses Chika, who is now working in South Africa, and You teases her about it. She later becomes AquaWhite once more when the wife of Greater Devil Emperor Barzaban, Greater Devil Empress Lilith, begins her quest for vengeance against the Aqours Rangers. Riko is glad to see Chika but gets embarrassed upon her sudden affection for the latter. Later on, AquaWhite faces Lilith on her own but gets badly injured and almost gets killed until AquaOrange saves but also gets badly injured. Riko states its best for them to surrender against the Neo-Akuma Empire but Chika convinces her and the team that their Wild Bonds are strong against the empire. AquaWhite, alongside AquaOrange and AquaBlue, they fight against Greater Devil Empress Lilith and defeated her with the Doubutsu Gattai Wild Aqours King. Riko gets sad that Chika will return to South Africa, as the latter staying for just a short time, but knows she will always be with her and everyone else through Wild Bonds.

Shoujo Kageki Revue Starlight VS Doubutsu Sentai Aqours Ranger
Riko now goes to the same university as Dia. Summoned by Wise Archangel Jacinda, Riko and her team head to Kyoto to save the Starlight Knights from Dark Demon Sotaro. She then teams up with Hikari Kagura/BlueStar to defeat Dark Hound and then teams up with their leaders to defeat the dark demon leader.

Mahou Sentai Nijiman VS Aqours Ranger
"'Is it okay if I could teach you my skills in archery, Yuki-san?'" Alongside her team, Riko has been chasing after Devil Prince Satan, who plans to rise up the Akuma Empire as the Neo-Akuma Empire. She then gets brainwashed into evil and fights with You against Ai Miyashita/OreNiji and Setsuna Yuki/AkaNiji until Sentsuna saves Riko. Later, AquaWhite teams up with AkaNiji with AquaBlue and OreNiji to defeat a revived Demon Hound and then defeats Devil Prince Satan for good. Afterwards, Riko offers Setsuna lessons on archery, which the latter accepts.

Love Live Super Sentai Wars
"'Did you know Chika is similar to Honoka as being idiots?'" Riko not only teams up the Nijimen again but with her predecessors, the Muse Rangers again. In the war, AquaWhite teams up with μ's2 (Eli Ayase) and KiNiji (Kasumi Nakasu). After the Infreshia Empire's downfall and when Ayumu comments Honoka could be legend among future Love Live Super Sentai teams, Riko says Chika and Honoka are both idiots, which offends Chika.