My-Otome Manga
In the manga's universe, Erstin's character is largely the same, including her crush on Nina and later Manshiro (a male body double of the real Mashiro) believing him to be a girl. But she is Coral No. 3 in the manga. This version of her character is noted as having F-cup breasts by Arika, and appears to suffer from androphobia, or fear of men, steming from past sexual harassment. This was due to drawing unwanted attraction to her larger-than-normal bust. Her oneesama is Shiho instead of Akane as in the anime.
She initially hated Arika for separating her from Nina because she had to move to another room to make space for Manshiro, which made her an easy victim for Shiho to manipulate into fighting for the Blue Sky Sapphire. She was the second of the initially ignorant to discover Manshiro's manhood, when she was an accidental witness to him urinating, a discovery that horrified her at first. However, after Manshiro protected her during a Schwarz attack, she managed to accept the truth, and falls deeper in love with him. She refers to his penis as an "elephant". Eventually, she "persuades" Natsuki to let her move back into the room occupied by Arika, Manshiro and Nina.
Unlike the anime, she is not a member of Schwarz. Although she comes close to death as a result of a self-directed suicide bombing aimed at Duran, she never actually dies. Eventually she gains a Meister Robe, the Rainbow Cloud Rhodonite ( 綵雲の薔薇輝石 Saiun no Barakiseki), of her own and is vital in defeating Fumi and the revived HiMEs.
In the Arashi spin off, she along with Arika and Nina act as Mashiro's maids, much to the students dismay. After her appearance, Arashi, Nagi's younger sister (thought to be male) invades the academy, and Mashiro makes her servant, and Erstin tried to use her sex appeal to defeat Arashi, however, her efferts were in vain, since Arashi was female to begin with, and was actually crossdressing at the time. Erstin was then sent out with cow as pushinment. Mashiro had walked in on theme, but apparently got the wrong idea, and quickly left. It is unknown what Mashiro was thinking at the time, Erstin, in her regret, cries to him that it was a misunderstanding.
Read more about this topic: Erstin Ho