Rosia (ロージア) is a member of the band Criticrista and is both the band's lead vocalist and guitarist.
She's also the student council secretary and honor student.
Rosia is a pale pink cat with slanted greenish-cyan eyes and a black nose. She has fuchsia cat ears and a tail, and long curling pink hair worn in pigtails, slightly darker than her skin. Her short bangs frame her face, and she has a long ahoge shaped like a heart. On her head she wears a pale yellow headband with a large red heart attached to each side. She wears a short white tube-top with a dark blue and white collar attached and the center cut out to shape a heart. Hanging from the collar is a pink gem heart attached to a pink and white striped bow, matching her frilly skirt. Also worn are sheer stockings with red pumps and ankle ribbons, a dark pink choker, and a dark pink thigh accessory with two bells attached. She also wears brown see-through leggings with red band and bells on each side with red high heels on the bottom and a red ribbon tied to her ankles. On each wrist is a fluffy pink bracelet, while hanging from her neck is a white two-tail cape with a gold heart design.
In Black Form, Rosia's hair turns fuchsia while her ears and tail change to purple. Her headband, shoes, and top turn black, while her skirt and cape turn grey. She loses her stockings while the ornaments of her headband turn into purple gem hearts. The bow at her collar gains a black stripe.
MofuMofu Rosia keeps her fuchsia hair but it lightens, as does her tail. She gains a pale pink cat-ear hood to match her pale pink fluffy paws on both her hands and feet. Her outfit turns into a pale pink dress and her bow gets its white stripe again, and her cape is made of fluff. The gem hearts on her head remain purple, and she gains dark mauve tights. Her eyes gain a slight design.
As Wedding Rosia, her eyes gain a sparkly design to them and her hair turns into a fuller detailed gradient. Her cat ears and tail soften in color and she wears a silver tiara with pink gems attached, one in the shape of a heart. On each side of her head is a ruby gem heart with a flowing white ribbon on its side. Her attire turns into a frilly, white and pale pink dress with ribbons attached to her wrists and ankles, with matching tights and shoes. She is shown holding a pink flower bouquet and gains several, petal like wings depicting a heart design on it, along with loose ribbons.
In the anime, Rosia appears the same. The only major difference is that her eyes lack the slant present with her design in the game. She is given a youthful appearance with a noticeable curvy frame.
She has a selfish personality, but due to her skillful gestures and ruthless behavior, many adore her. However, deep down, she is actually a very nice person who loves her friends. As seen on the last two episodes.