Esal leads Kazalumu Beast Sanctuary as headmistress, directing the training of beast doctors and the care of Royal Beasts. Her leadership confers substantial authority over sanctuary operations and educational policies. A long-standing friendship with Joeun, Erin's adoptive father, shapes her choice to admit Erin as a student despite potential controversy.

When Erin enrolls at Kazalumu, Esal assigns her to care for Leelan, an injured young Royal Beast refusing food and facing death, overriding staff objections about Erin's unconventional methods. Esal recognizes Erin's unique understanding of Royal Beasts after observing her use harp sounds to stimulate Leelan's appetite, mimicking wild Beast communication. She supports Erin's rejection of traditional tools like the Silent Whistle paralysis device and the tokujisui potion mandated by the Royal Beast Canon.

As Leelan forms an unprecedented bond with Erin and regains abilities like flight—previously unseen in captivity—Esal shields Erin from political pressures seeking to weaponize this relationship. She advocates for Erin's right to raise Leelan according to natural behaviors rather than enforced obedience protocols.

Years later, following Erin's graduation and appointment as a Kazalumu teacher, Esal remains headmistress. She collaborates with Erin's former classmates, like Tomura, who also become teachers. Her duties expand to managing challenges like the reluctance of young Royal Beasts born in captivity to breed. During this time, she interacts with Erin and Ialu's son, Jeshi, expressing concern over the boy's unsupervised approaches to dangerous Royal Beasts. She implements safety measures restricting Beast access when necessary for his protection.

Throughout the sanctuary's evolution, Esal consistently prioritizes the well-being of both Royal Beasts and students, balancing institutional requirements with progressive approaches to beast management. Her tenure spans decades, enduring political conflicts and generational shifts within Kazalumu.