Cerval (Japanese: セーバル Hepburn: Sēbaru), initially identified as Fake Serval, is a major character in the original Kemono Friends game. She is the Cellien counterpart of Serval, and much of the game's plot is focused on their interaction.
Cerval is a Cellien-like mirror of Serval, possessing a very similar appearance. However, there are several differences - her skin and clothes are, for the most part, green. The ears are unlike a real serval's ears in all regards, and are more reminiscent of large wings. Like other Celliens, her ears have a gradient, going from green, to yellow, to red, and finally to blue. Her skirt is tied with a single ribbon, whose tips also end in a gradient. Her shoes, unlike Serval's, have no ribbons at all. Her eyes are red, and are drawn with a distinct outline, and the 'M' pattern on her forehead is not only distinctly shorter, but it glows white. Her hair is 'rounder' instead of having sharp ends like Serval's, possibly to represent the 'rigid and wiggly' texture Celliens have.
Her original version as a Cellien is still similar to Serval, but incredibly simplistic. It could be described as more of a 'silhouette' of Serval's than a mirror image. The ears aren't like 'wings' at all, but they still have their gradient. It lacks any sort of distinctive spots or Serval-like marks, including the 'M' pattern - the shirt even seems to lack sleeves, and integrates itself into the body of the Cellien instead. It lacks ribbons or any sort of other decor at all. Unlike her Friend form, the feet and the tail still have a gradient.
Cerval is introduced as a mysterious Serval-like Cellien who often gets herself into trouble, to the chagrin of the actual Serval who ends up receiving the blame. Her speech patterns are slow and vague, featuring heavy usage of ellipses and disconnected, incomplete phrases characterizing much of her dialogue in the story. She initially speaks only in Katakana, a literary device employed by Japanese writers to denote that a character's way of speaking is robotic or even possessed.
After her initial confrontation (and battle), she is not particularly hostile or aggressive, instead concentrating on returning to the side of the Cellien Queen with all due haste. Despite this, however, she is prone to becoming distracted, especially by Japari Buns, a fondness that she shares in common with Serval. It's revealed in the process that there are a great many things she does not understand, but she gradually learns from her experiences over the course of the plot and develops her own identity.
Throughout the story it becomes clear that, despite her Cellien background, Cerval is not an enemy and even comes to identify Serval as a friend. This becomes a source of conflict in the story as the only half-aware Cerval is torn between her instinctive loyalty to the Cellien Queen and her newfound friendship and experiences with Serval and the other characters comprising the protagonist's party.
After becoming a Friend, Cerval's personality transforms and becomes more defined, with her speech patterns becoming more normalized and comprehensible, albeit still brief. She is eager to do her best in battle and have new experiences, and is particularly vocal about her love for her bonds with Serval and the protagonist.