Sunil was among the first mundanes to try for Ascension after over a decade of no Ascension due to the Mortal Cup being missing, thought to be destroyed. Because of the Cup's retrieval and the dwindling of Shadowhunter numbers in the Dark War, Sunil was among several other aspirants.
Sunil was assigned to a room in the basement at the Academy, along with the other mundanes and students in the "dregs" stream, down the hall from George and Simon's room. At one point, he became friends with Simon and his group.
When Isabelle Lightwood came to visit the Academy with her father, the Inquisitor and guest lecturer Robert Lightwood, Sunil tried very hard to catch her attention. When Isabelle invited the students to get in trouble with her, Sunil was among the many students who excitedly joined without much convincing. He also helped coax Simon into joining them, upon Isabelle's request. When Isabelle told them that they were going to summon an imp demon, Sunil remained a willing participant. When it was later revealed to be a test and were chastised for their choices, Sunil shamelessly asked if they would be graded for it.
On the day before Sunil and nine other students from their class were set to Ascend, the idea of potentially dying from drinking from the Cup proved too much for him and he decided not to go through with it. He left the Academy that night without saying goodbye to his friends and instead had Milla pass on a note to them to explain his departure. Two other students (Leilana and Boris) left that night. His friend Marisol Garza resented his decision.
Sunil is said to be somber and serious. He is also considerably a practical thinker who made a decision to save himself and abandon trying to be a Shadowhunter; this may mean he thought long and hard about it, or may have made an impulsive decision to not go through with his Ascension.
- Nothing but Shadows (first appearance)
- The Evil We Love
- Born to Endless Night
- Angels Twice Descending (mentioned only)
- Sunil has four pet rabbits that he always talks about and was always particularly concerned about little Ringo getting picked on by his bigger brothers.
- Sunil admires Alec Lightwood, who inspired him to want to become a Shadowhunter.