" You are going to pretend to be me, and sing on stage for the first half of the concert !!! "
Like Urabe, Momoka has an average sized body for a typical teenage girl. However, her body has developed into a mature, erotic, adult-like figure and appearance. She is somewhat thin, but not lanky, and has a proper weight for her body size and shape. She has a round face with a slightly pointed chin. Momoka has huge 'anime girl' eyes. Her eyes are narrow and vertically oval, with a dark greenish-brown color. Her hair is milk chocolate brown, with golden and dark chocolate brown highlights. She has an average neck, but narrow shoulders. Her bust size is smaller than Urabe's, but unlike Urabe's, is of a 'muffin top' shape, just like that of a tween girl. She has a narrow waist, really shown off by her bare-midriff stage costumes. Momoka has long, lean, shapely legs, well developed by use of them for the high-kicks. She has average feet. Her small hands seem much larger when she wears gloves and handles the wireless mic at her concerts.
Momoka wears a wide verity of fashion styles and outfits, with many of them giving off a sexy, erotic appearance. On the day that she meets Tsubaki and Urabe, she is wearing a colorful, skull logo polo shirt, a pleated, plaid, mirco mini-skirt, black knee-high socks, and athletic shoes. Another time Momoka wears a striped, V neck, mini-hemlined T-shirt dress. Now because the two girls are the same body size and shape ( except for the bust size ), that means that Momoka can wear Urabe's female high school uniform ( she does ! ), and Urabe can wear Momoka's rock star stage outfits and costumes ( she does, with some allowance for her larger bust ! ) !
For all her popularity and notoriety, Momoka is still very much an ordinary girl, who like most teenage girls, has at this point in their life many good points about their personality, but a few bad traits, too.
Momoka is very impetuous. She sometimes acts rashly, without thinking things through, or giving people the benefit of the doubt, or a chance to defend themselves. As soon as the male passenger and herself got off the train, she gave him a high-kick to the head without any warning, or without any time to sort things out as to just what happened. The guy was probably a pedophile anyway, but Momoka wasn't about to delay any retribution to him, given this streak in her personality. Now one knows why she has to wear leg restraints, because this gives her a chance to hopefully think before releasing and offering up a high-kick.
Being a Rock Star and Singing Idol, Momoka is also a bit self-centered. She, for the most part, enjoys performing on stage, and does so on her own terms, but she also yearns to be a "normal girl", and focuses her attention on that possibility, even if it might be a selfish motive. This yearning for a different life leads Momoka to be devious at times, tricking people as to her true nature. She wanted so bad to experience the Drool Bond that Urabe and Tsubaki enjoys, even if she is not sensitive to drool, such that she resorts to trickery to get to do it with Tsubaki. This also shows that Momoka is conflicted in her heart and soul, indecisive about her life's course of action, that of an Idol who is a celebrity out in public, or that of an ordinary but cute high school girl who never stands out in public.
Momoka has good qualities, too. She is appreciative of what friends and other do for her, at least to some degree. For as much as Urabe has done for her, she seems to value her offers of help, even if not all of them are what Momoka wants. Although in need of more work and adjustments, her sense of fairness is seen when she was willing to go back to her career as an Idol, even though she would more likely want to stay as a high school girl, wear the female school uniform, and go to school every day so as to interact and have real friendship with both boys and girls.
Not counting the fact that Momoka has brown hair and much smaller breasts, there is no real physical difference between herself and Urabe. This allows the girls to potentially pose as each other, which Momoka comes to realize as a possibility, and confronts Urabe personally in hopes that she will agree to her plan of switching between model and high school student ( similar to the story of The Prince and The Pauper ). Urabe, however, completely turns her down, not being interested in experiencing the life of an idol. But after a quarrel breaks out between the two, which heats up and ends with Momoka's clothes being shredded by Urabe's scissors, and Urabe is on the receiving end of a high-kick, Urabe actually takes her to her home, where the girls make up with one another and further become acquainted with each other.
After seeing Urabe and Tsubaki's Drool Bond, she goes with her promise and supposedly lets go of her plan to switch places; however not before stealing Urabe's uniform and and using it to go through a ruse to make Tsubaki taste her drool. It is later revealed she wanted to become a "normal" girl, this due to an incident with a boy she had a crush on before she became famous. Then after being discovered and becoming famous, she finally worked up the courage to confess her feelings to him. But before they kissed to seal the deal, he asked if he could tell his friends he was dating a famous girl. Realizing he only ever liked her because she was famous, she high kicked him in the head, and that was the end of their shipping.
She appears again during the Mysterious Movie Production arc in the manga, posing as Urabe and helping promote the high school's film club's movie.
Virtual "Twins" with Mikoto Urabe
Similarity between Momoka and Urabe is so significant that they are essentially "twins". In terms of their appearance, there is no real difference between them, except their hair color and breast sizes. If one or the other puts on a wig, or dyes her hair to match, and then hides her breasts under clothes, many people are unable see difference between them. When Momoka is introduced in the manga story, she is shown giving a male pedophile a kick to the head on a train platform, for attempting to grope her on the train. Many in the audience get the impression that it was Urabe that gives out the high-kick. Even those as close as Tsubaki, or Momoka's manager, cannot tell the difference.
Their similarity, however, goes even beyond physical appearance. Similar to how Urabe uses scissors in defense, Momoka displays high kicks, and is forced to wear restraints. Both devices the girls then hide near their panties.
Another thing is that both girls have similar abilities to perform as idols. Although Momoka is little more convincing here due her experiences, still, Urabe is good enough to hold the audiences attention during the first half of a big concert on her own, performing on her natural talent alone. Original tagline of chapter 39 even suggest that girls could form singing unit, if they wanted.
But in terms of their personalities, the girls have similarities, but some differences too, that being mostly while Urabe is more calm and reserved, Momoka is more energetic and lively.