Mayuyu has long, pigtails with pink ribbons, blue hair, a cybernetic right arm that launches missiles, and rose-colored eyes. She also usually wears a scrunchie on her left arm. Like all members of AKB0048, she has a heart-shaped lining on her hair and eyes. When trouble, such as DES approaches, her pigtails stand on end.
In the manga, she has medium, blackish blue twin tails with blue ribbon. She has blackish-blue eyes.
Mayuyu acts cute in front of the crowds, giving the impression of an energetic and bubbly personality. In truth, she's a relatively emotionless girl, speaking in a monotone voice and has little social contact with the others. However, her emotions are extremely difficult to predict as she has a poker face personality. If there's no more food, she'll threaten Chef Papa until he gets her more food. Whilst it is never explicitly stated, she's heavily hinted to be a cyborg or even an android as she is the only one classified as MK3 Mayuyu .
Mayuyu, along with the rest of AKB0048, hold a secret concert in an abandoned mine on Lancastar. The DES tried to stop them, but AKB0048 quickly defeated them before leaving Lancastar.
4 years later, Mayuyu and the rest of AKB0048 appeared on a hologram card that Yuka had received, telling them how to do the auditions.
Later, Mayuyu and the rest of AKB0048 came to the rescue of the auditioners when the DES took over a ship in order to search and capture the auditioners. While fighting a DES mobile, Mayuyu revealed that she has a cybernetic right arm that can launch missiles, making Orine think that Mayuyu might be a cyborg.
They managed to rescue the auditioners, defeat the DES and making an escape on their ship before the DES could catch them.
Mayuyu next appears in Episode 3, where Sayaka is force feeding the girls steaks to keep their energy up. Mayuyu has already consumed twenty.
Mayuyu appears in Episode 5, first in the cafeteria where she terrorizes Chef Papa for not have enough food, then in the bath with Suzuko and Sonata, where she mentions Sensei Sensei, then torments Sonata for taking her extra helpings at breakfast. Later, Mayuyu finds out that Kanata will replace Takamina.
Mayu Watanabe was born on March 26, 1994 in Saitama Prefecture, Japan. She was a original member of AKB48's Team B sub unit as of 2006 until the 2012 Team Reshuffle, which moved her to Team A, and is also a part-time actress. She has a solo career and is part of the Sub-Unit Watarirouka Hashiritai 7. She has a passion for things that are pink and cute, and is said to resemble her mother. She is an anime otaku and is also the voice actress of Chieri Sono. She is known as "Cyborg Idol"/"Cyborg Girl" (CG).
Mayuyu is based on current AKB48 member Mayu Watanabe. In addition to serving as the inspiration for this character, Mayu is also the voice of Chieri, making her the only member of AKB48 to voice a character in the series and have a character based on them.
Mayuyu is the 3rd person to hold that name in AKB0048, although her title is Mayu Watanabe MKIII/Type 3
This is because Mayuyu is more likely an android. In the drama CD contained along with opening and ending song single, she pointed that she was 'made' for the sake of Mayuyu position.
The real life Mayuyu holds the nickname "Idol Cyborg" / "Cyborg Girl" (CG) because of her expressions, and she is really good at hiding her emotions.
In Episode 17, she ranked 5th at the General Elections, but was previously ranked 4th in the early rankings.
She is always seen accompanied by Yuki Kashiwagi. The real life Mayu was always accompanied by the real life Yuki as well.
Both Mayuyu and Chieri own stuffed alpacas, again pointing out the fact that the real Mayu Watanabe voices Chieri.
Her missile-arm may be a reference to an episode of AKBingo where Mayu lost a dodgeball game and as punishment, had her arm "cut off" in a prank.
Mayuyu probably has been a successor for a very long time, as she can be seen on the same stage as Acchan, and is only the third successor of the original Mayuyu.
In one of the audio dramas, Suzuko show images of MK3, as well as MK2 to the other members of NO NAME, and it's stated that they are identical.