Crocell Kerori is a student at Babylus Demon School. She attends the same class as Iruma Suzuki and his friends, the Abnormal Class. Normally under the guise of an ordinary-looking freshman student, she has an Akudol alter-ego named Kuromu (くろむ ).
As a student, Kerori looks quite different than her idol counterpart. Her hair is white and her horns are small and black, peeking out from beneath her hair. She wears a white girl's uniform in the sailor style, with a distinct Sailor moon-esque red bowtie. She has white stockings and a red skirt. Her most distinct feature, however, is her large, round spectacles, which contain the ability to disguise her appearance to other demons.
As an idol, Kerori wears a violet-colored wig, which turns gold at the ends, and is cut in a rough bob style at the front, with a long ponytail at the back. It also has horns that disguise her normal ones, and are longer and curled, rather than her normal, short stout horns.
She wears a typical idol dress, with a puffed pink and blue skirt, and a black and purple corset. Around her neck hangs a purple bat-wing suit tie fastened with a pink bow-tie. She also wears thigh-high white stockings ending in heavy boots. She has small purple wings, and wears no glasses.
Her eye color is blue, which is a consistent feature between both appearances.
As a child, Kerori possessed very weak magic power. This meant that, in comparison to her siblings and family, she was never able to meet their expectations or make any meaningful achievements. This led to a lack of self-esteem, where she despaired at being a failure and a shame to her family name. This changed however, as she slowly began to notice that the way the demons on the street treated her. Spoiling her, treating her nicely, she realized they were paying attention to her and treating her well because of her adorable appearance.
She quickly discovered the existence of Akudols, and came to the realization that she could use her looks and physical abilities, rather than her magical ones, to become a top Akudol, and prove herself in her family's eyes. Since then, she has led a double life, switching between Kuromu and Kerori between Idol work and school. She is currently the top student-age idol in terms of popularity.
Ice Surface - A Bloodline Magic; Kerori can adjust the temperature of water, particularly in cooling even in the air to lower temperature and create ice for offense or defense. This is at her disadvantage when she is easily triggered by emotion with overuse that results in a fever which requires specific medical attention or someone with the same ability to lower down the side-effects.
Immense Beauty - A skill garnered during Caim Kamui and Kerori's intense special training; she was able to emulate Beauty image to entrap both demons and animals to her authority, dominating them on will. This control can only be sustained when her cute and bubbly form are disintegrated. 
Iruma Suzuki -
- In demonology, Crocell (also spelled as Crokel and Procell) is a Duke of Hell, having 48 legions of demons under his command. He can teach geometry and other liberal sciences, warm bodies of water, create the illusion of the sound of rushing waters, and reveal the location of natural baths. He is depicted as an angel with a tendency to speak in dark and mysterious ways, and is associated with the element of water.
- When Kerori is nervous or upset, she clenched her hand with her thumb under fingers.
- Iruma-kun knows of Crocell Kerori alter ego Akudol Kuromu, but keeps it a secret, as he has a secret as well.