Jamil Viper is a second-year student at Night Raven College and serves as the vice-warden of Scarabia dormitory. He was born into the Viper family, which for generations has been bound by indentured servitude to the wealthy and aristocratic Asim family. As a result, from early childhood, Jamil was assigned to be the personal attendant to Kalim Al-Asim, the heir to the Asim family fortune. His parents instilled in him the expectation that he must never outshine Kalim, often scolding young Jamil for winning games against his master or displaying his own natural talents. This upbringing forced him to constantly downplay his achievements, hide his intelligence, and suppress his own ambitions to avoid causing offense or jealousy.

Outwardly, Jamil presents himself as a capable and loyal attendant who diligently manages Kalim's needs, often cleaning up the messes caused by Kalim's oblivious and carefree nature. He appears to be an ordinary student who achieves perfectly average scores in his classes, but this is a deliberate act of self-sabotage to avoid drawing attention to his true potential. Beneath this calm and dutiful exterior lies a deeply resentful and calculating individual. Jamil harbors a simmering hatred for Kalim, not for any malicious intent on Kalim's part, but for his master's blissful ignorance of the suffering his position causes Jamil. He resents having to live in Kalim's shadow, watching his master naively enjoy privileges and recognition that Jamil believes he himself has earned through silent, unacknowledged effort. This resentment is compounded by dangerous incidents from their past, such as when Jamil fell into a two-week coma after taste-testing Kalim's curry for poison, an experience that, ironically, did not diminish his love for curry.

Jamil's role in the story becomes pivotal during the winter holidays, an arc that the anime adaptation is expected to cover. While most students leave campus, Jamil executes an elaborate scheme to depose Kalim from his position as dorm warden. Using his unique magic, he places Kalim under a hypnotic spell, transforming the normally cheerful and benevolent warden into a tyrannical and demanding leader. Kalim then imposes a harsh, mandatory study and training regimen on the rest of the Scarabia dorm, trapping the students on campus. Jamil's plan is to turn the dorm against Kalim, forcing his removal so that Jamil can step into the role and finally gain the recognition he craves. The scheme is ultimately uncovered and thwarted through the combined efforts of the Ramshackle Dorm's prefect, Grim, and several students from Octavinelle dorm. When his plan collapses, Jamil is cornered and forced to confess his manipulations publicly. The stress and accumulated negative emotions cause him to undergo an overblot, a dangerous state where a mage's magical energy spirals out of control due to overwhelming negative emotions. In this volatile state, he unleashes years of pent-up fury, accusing Kalim of stealing everything from him and admitting he had long wished for Kalim to simply disappear.

The most significant relationship in Jamil's life is his complicated bond with Kalim Al-Asim. It is a dynamic built on a lifetime of servitude, care, envy, and a profound lack of understanding. While Jamil is responsible for Kalim's safety and daily needs, including cooking all his meals, he also views Kalim as a gullible, foolish obstacle who has unknowingly stolen his rightful destiny. Kalim, for his part, genuinely considers Jamil a close friend and is oblivious to the depth of Jamil's animosity, fondly remembering their shared childhood games while Jamil recalls them as exercises in forced submission. After Jamil's overblot and defeat, a critical shift occurs. Jamil still chooses to serve Kalim, but the nature of their relationship is redefined. He resolves to no longer hold back his true abilities, and Kalim, now aware of Jamil's grievances, accepts this change and vows to compete with him as an equal rather than an oblivious superior. Their relationship transitions from one of forced subservience to a more overt rivalry and partnership.

In terms of personal development, Jamil's arc is a story of liberation from a stifling role. He begins as a character who sees no way out of his predetermined life except through manipulation and sabotage. His defeat and subsequent overblot serve as a violent but necessary catharsis, forcing his hidden feelings into the open. Afterwards, he begins the difficult work of integrating his true, ambitious self with his role as an attendant, refusing to fade into the background any longer. This journey reveals a person who is fiercely intelligent, proud, and desperate for autonomy, a sharp contrast to the unassuming servant he pretended to be.

Jamil possesses considerable abilities that he intentionally conceals for much of the story. His unique magic is called Snake Whisper. This powerful hypnosis allows him to control the minds of those who meet his gaze, capable of issuing complex commands to multiple individuals simultaneously for extended periods. However, the use of this potent magic accumulates blot (a magical pollutant) very quickly, directly contributing to his overblot when he is forced to use it extensively. Beyond his magic, Jamil is highly intelligent and a master strategist, capable of orchestrating complex, multi-step plans. He is also physically adept, excelling in athletics as a member of the basketball club and a skilled breakdancer, a hobby he pursues with passion when free from his duties. His talents extend to practical skills as well; he is an excellent cook, a necessity born from managing Kalim's household, and possesses sharp observational skills that allow him to identify flaws and solve intricate problems, such as perfecting complex potions that even the top students struggle with.