Eve Speed is a supporting character known as the strongest gladiator in the royal capital of Monroy. She is a female of the leopard beastfolk, and her appearance includes traits such as armor, a sword, gloves, and a leopard motif. Her past is marked by immense tragedy, as she is the sole survivor of her tribe after it was wiped out during an attack. In her search for safety following this destruction, she eventually became a slave, fighting in dangerous coliseum tournaments to earn her freedom.

In terms of personality, Eve is strong-willed and brave, possessing a fighting spirit that never gives up even when facing the hardest battles. Despite her tough and brutal past as a slave and gladiator, she cares deeply about her friends and displays a protective, almost maternal side, particularly towards a young dark elf girl named Lisbeth, whom she lovingly calls her little sister. Her primary motivation within the story is to secure her freedom and protect those she cares about. Her immediate goal when she appears is to rescue Lisbeth, a young slave who was being cruelly mistreated by her mistress.

Eve's role in the story begins as a powerful but trapped combatant in the capital. Her path crosses with the protagonist, Touka Mimori, when he and his companion Seras Ashrain attempt to convince her to flee with them rather than fight to her death in a rigged coliseum match orchestrated by a corrupt Duke. After Touka saves her and Lisbeth from this deadly conspiracy, Eve becomes a close and loyal ally to him, joining his group as they continue their journey. She develops a close bond with Lisbeth, who is extremely polite and refers to Eve as big sister. While Eve takes an active role in combat as a formidable swordswoman, Lisbeth does not fight but supports the group by cooking and carrying baggage. Her character development sees her transition from a solitary survivor fighting for her own freedom to a trusting companion who fights alongside others for a greater cause. Her notable abilities are rooted in her physical prowess, as she is recognized as the strongest gladiator in the royal capital, utilizing her agility, sword skills, and likely the enhanced physical traits of her leopard beastfolk lineage in combat.