Cinderella is a feminine humanoid robot with long mechanical extremities and a spherical lower body, lacking legs in the anime. It has pronounced breasts and a thin waist while wearing a top resembling a bra. Its eyes resemble fashionista glasses, with the top of its head being similar to a beehive hairstyle.
Color Schemes
The series is known for alternating colors between media, the information presented below may or may not be canon.
Colored MangaAnime
Body
(Hot and light pink with yellow accessories. Pink-tinted gray extremities.)
Eyes(Hot pink)
Body
(Light pink head and breasts. White faceplate and hands. Red body and elbow joints. Black accessories. Yellow extremities.)
Eyes(Magenta)
Abilities
Cinderella's abilities are centered around cosmetic work and are exclusively used in that regard. It hasn't been shown to have any potential outside of Aya's work.
To understand Cinderella, one must learn about physiognomy, a pseudo-science placing significance on one's facial features. Aya Tsuji exposes her belief that the fortune of an individual depends at least partially on their face. Thus by changing the face, specifically molding it into a "joyful face", Aya can effectively alter their fate and even choose what kind of love life her clients will have.[2] This belief also applies to palmistry and podomancy among others.[3]
Body Part Replacement
Cinderella replaces body features for more favorable ones
Cinderella is able to replace some parts of one's body by creating a replacement for it from the slots on its hand and then sliding the hand into the body to replace said part.[2]
Determining what a client should look like via a computer program,[2] Aya can then modify whatever has to be replaced at her leisure. Because of the theory of physiognomy, she can change their love life in any way she's been paid to do. This is first seen performed on Yukako Yamagishi whose slight "Finding Love" enhancement causes her to accidentally have a date with Koichi.[4]
The client must remain immobile, or Aya may botch the replacement process. The effects are temporary, and last only 30 minutes.[4] Aya uses this weakness as a business tool to push her clients into coming back.[3]
Those who are affected the clients change will feel an unexplainable attraction that may vary in intensity regardless of what they look like, which soon stops as soon as 30 minutes pass.[4] Even an ugly woman with a joyful face has had her lover propose to her.[2] For a "Capturing Love" enhancement, Koichi viewed Yukako as literally dazzling with beauty. Later, events conspired to unite the two.[5]
Cinderella can also remove body parts from existing humans and place them on others, as done with Yoshikage Kira to disguise him from Josuke and Jotaro.[6] In this case, the effects are permanent and persist even if Aya dies.
Cinderella remembers every face it has beautified and as a result, can generate an exact template of one's former face, as well as generate a large amount of them, which will float around Cinderella.[7]
Permanent Body Replacement
In the case someone wants to permanently modify themselves, several additional rules apply. Because altering one's fate properly and for a great amount of time requires a lot of energy,[3] one must show the dedication to match. Thus after being modified, one must apply a special lipstick every 30 minutes for 24 hours except when sleeping to keep the enhancements.[3] The lipstick acts like a protection that contains the energy necessary to change Fate.
However, if the lipstick is not applied at the required point in time, it will deform the face of the recipient of the effect into ugliness as punishment for not keeping their word, then all modified body features will gradually disappear. Aya explains it saying the failure of applying lipstick causes a leak of energy and thus the collapse of the body.[8] However, Aya is able to fix the body if she wills it.
Cinderella's namesake confirmed in Vol.16 "Shueisha Jump RemixDiamond is Unbreakable Edition"
Trivia
Cinderella's function to make people more desirable to a potential love interest refers to the children's tale of the same name where the Fairy God Mother gives Cinderella a beautiful dress that will disappear at a set hour.