Manyuu, Chifusa

魔乳千房

Chifusa Manyuu is the tomboyish heir to the Manyuu clan and a skilled samurai. She is hot-tempered, impulsive, and moody, yet deeply loyal and kind-hearted; however, her time with her mother has left her easily attracted to busty women. This tendency often puts her at a disadvantage against the assassins hunting her, as she is readily distracted by their "assets."
Although she was intended to uphold the Manyuu tradition, she abandons her family due to her resentment of their unfair governance system (which judges a woman's worth by her breast size). She also steals the Scroll of Secrets, which contains techniques for enlarging breasts.
Chifusa is a curvy ninja girl with golden eyes and blue hair, typically tied up in a ponytail. She frequently wears a white scarf with a loose red kimono that is slightly open at the top. At times, she wears a cloth wrap beneath her top to hold the Manyuu scroll, which may also serve to restrain breast growth or hide their true size.
Despite her young age, Chifusa's body appears curvaceous. This only serves to make her wide hips, thick thighs, prominent buttocks, and massive breasts even more striking, giving her the silhouette of a mature woman.
She is the only person capable of a technique called Breast Flow, which allows her to control the shape of breasts, enabling her to enlarge or reduce them. Due to her lack of experience with the technique, she can initially only use it to absorb other women's breasts. After discovering this ability, Chifusa sets as her ultimate goal to master it so she can ensure all women in Japan have a decent-sized bust.

Spoiler

A key aspect of her personality is her dislike of large breasts, the way people are treated based on having them or not, and how manipulative people with them can be (such as busty girls at a maid cafe).
During Chifusa's orgasm, her young breasts enlarge and engorge to such an immense degree of fullness and sensitivity that they essentially become udders. This new form comes to be known as Chifusa's "Oppai Maximum."
When in Oppai Maximum, Chifusa takes on more mature features, such as wider hips, thicker thighs, plumper buttocks, and large breasts with erect nipples. Her areolas also become noticeably fuller and perkier as the show progresses. This is likely due to her breasts producing and being full of milk. Her enhanced sexual characteristics give her the silhouette of a fertility goddess.
Changes observed when in Oppai Maximum form:
Massive engorged breasts (larger than her head, requiring two hands to hold)
Increased handouts, affection, and social status due to said massive breasts
Extraordinarily sensitive erogenous zones
Incredibly stiff and constantly erect nipples
More pronounced and plump areolas
Milk production
Increased libido
Ability to reach climax via breast and nipple stimulation alone
Increased metabolism (heart rate, sweating, salivating)