Eris is a recurring character in Tsukimichi -Moonlit Fantasy- who belongs to the Forest Ogre race and works for the Kuzunoha Company. Physically, she is short with light-brown skin and shoulder-length gray hair that includes bangs reaching her eyes and nose. Her red eyes tend to appear very expressionless, and her perfectly horizontal eyebrows often give her a sleepy look.

In terms of personality, Eris can be very easy-going, a trait that sometimes causes problems for others. However, she also demonstrates moments of being a creative genius who comes up with strange and unconventional ideas. Like other Forest Ogres, she was initially hostile toward other races, reflecting her tribe's isolationist nature before encountering the protagonist. The series sometimes positions her as a comic relief character, though she can be surprisingly helpful when the situation demands it.

Eris's role in the story begins when she and her fellow Forest Ogre Aqua encounter Makoto Misumi and Mio in the Tinarac Forest. Perceiving them as threats to their home, Eris and Aqua launch an attack, only to be quickly overwhelmed by Makoto's power. Following this confrontation, they learn that Makoto is not an enemy, apologize for their actions, and lead him to their village. This meeting leads to peaceful relations, and eventually both Eris and Aqua join Makoto's growing community.

Once part of Makoto's group, Eris undergoes harsh training under Tomoe and Mio alongside other Forest Ogres, a regimen so intense it is often described as hellish. She later takes on important responsibilities in Makoto's business operations, serving as both a guard and salesperson at the Kuzunoha Company shops in Tsige and later Rotsgard, ensuring safety and smooth operations while interacting with customers.

Eris's key relationships include her close partnership with Aqua, a fellow Forest Ogre who shares similar duties and training experiences. The two of them were initially in charge of killing or capturing any hyumans who entered the Tinarac Forest before joining Makoto. Within the Kuzunoha Company, Eris works under the larger organizational structure led by Makoto and his primary servants Tomoe, Mio, and Shiki.

Regarding development, Eris transitions from a hostile forest guardian opposed to outsiders to a loyal employee of the Kuzunoha Company who protects its shops and assists with daily operations. Her training period in Asora, Makoto's pocket dimension, represents significant growth as she adapts to new living conditions and forms alliances with formerly unknown races.

In terms of notable abilities, Eris is a formidable warrior among the Forest Ogres, though not on the level of Makoto or his most powerful servants. Her magic centers around the element of water, which she manifests in the form of ice for both offensive and defensive purposes, as well as for influencing nature. Together with Aqua, she created the spell Floral Ice Prison, an ice barrier described as nearly impenetrable by conventional means. Additionally, Eris serves as a type of medium for the deities Daikokuten and Athena. She possesses a wide range of wavelength that enables these gods to send her messages and visions, through which the Floral Ice Prison dance and uniform were created.