Feresu operates as a frontline operative for the mercenary group Escape Shop Extractors, also known as Nigashiya. Her specialization involves facilitating client escapes from isolated city sectors called clusters. A member of the demon tribe, she is approximately 17 years old and distinguished by her pigtails.

In combat, Feresu functions as a "Gun Wizard," leveraging firearms proficiency and athletic agility combined with spells that manipulate bullet trajectories. This expertise makes her a critical asset for tactical operations requiring ranged combat support.

Academically, she maintains a civilian cover as a high school student attending school within the Ochanomizu cluster alongside her teammate Equa. While superficially stubborn, her underlying personality reveals shyness and a tendency to be easily influenced.

Her background includes prior affiliation with the Kanto Union, a yakuza organization controlling the Shinjuku cluster. This history surfaces when the group's leader, Toichi, requests extraction assistance, visibly unsettling her due to their shared past.

Missions occasionally see Feresu trigger significant complications, such as violating religious prohibitions within the Odaiba cluster and inadvertently escalating a routine operation into a pursuit by enraged devotees. She demonstrates her capacity to function within the team framework during Equa's absence due to illness, participating effectively in executing extraction protocols without leadership oversight.