Cayenn is a prominent character in the Paldea region, known for serving as a member of the region's Elite Four, where she specializes in Ground-type Pokémon. Her first appearance takes place within the halls of Naranja Academy, where she is introduced alongside another Elite Four member. She later becomes a key participant in friendly multi-battle exercises designed to demonstrate Terastal training.

In terms of appearance, Cayenn has an androgynous look characterized by her green hair tied into a long ponytail, with longer strands left loose on the left side of her head, and red eyes. Her attire typically consists of a beige button-up shirt with rolled-up sleeves, a black tie held by a triangular pendant, matching black suspenders, dark long pants, and brown shoes. She also wears triangular hoop earrings and circular piercings. A notable part of her outfit is her black gloves, which bear the compass logo of the Paldea Pokémon League; she wears these specifically to handle her Clodsire safely, as the gloves prevent direct contact with its poisonous skin.

Cayenn possesses a personality that is generally calm, kind, outgoing, and somewhat prone to teasing. However, she is fully capable of becoming quite serious when the situation demands it. Her empathy is particularly evident in her interactions with newer or less confident trainers. For instance, before a battle with the young trainer Liko, Cayenn notices that Liko is overwhelmed by nervousness and uses lighthearted jokes to help her relax, demonstrating a clear sense of care and patience. She prefers to wait until her opponent is at ease before beginning a serious fight.

Cayenn's role in the story is primarily as a formidable opponent and a catalyst for growth. She takes part in exhibition matches against other skilled trainers, including fellow Elite Four members. More significantly, she battles directly against Liko and another student named Araceli. In this battle, her skill and strategic thinking are put on full display, using her Pokémon effectively to secure victory. Beyond just winning, her role serves to deepen Liko's understanding of Pokémon battles. After their match, Liko thanks Cayenn for helping her reflect on her reasons for battling, noting that Cayenn made her grow to like Pokémon battles much more. Cayenn is also present as a spectator for other crucial student battles, watching important tournaments and matches that determine access to restricted areas like Area Zero.

Her key relationships include her fellow Elite Four members, with whom she is often seen alongside. She also has a notable rapport with the student Liko, acting as both an intimidating opponent and a supportive mentor figure who helps build confidence. Her connection with her own Pokémon is also essential, especially with her Clodsire, which requires special handling due to its toxic nature.

Throughout her appearances, Cayenn demonstrates notable abilities as a trainer. Her expertise in Ground-type Pokémon is evident through her use of Pokémon like Clodsire and Dugtrio in battle. Her strategic acumen is shown in multi-battle formats, where she coordinates attacks effectively, such as having her Dugtrio use moves like Dig and Avalanche. She is also proficient in using the Terastal phenomenon, having been shown to Terastallize her Clodsire during a critical moment in her battle against Liko to counter the opponent's Grass-type moves. Her calm and sometimes aggressive battling style when the situation becomes tense reinforces her status as a member of the Elite Four, highlighting the high level of skill expected from a trainer of her rank.