Ken Amada is a ten-year-old elementary school student who becomes the youngest human member of the Specialized Extracurricular Execution Squad (SEES). An orphan with no remaining family after his mother's death two years prior – officially reported as an accident – he lives at the Iwatodai Dormitory after an invitation from Shuji Ikutsuki. Unbeknownst to SEES initially, Ken joined the group concealing a motive: to avenge his mother, having witnessed her killed during a SEES mission when Shinjiro Aragaki's Persona, Castor, went berserk. Despite his youth, Ken displays pronounced maturity and politeness, frequently employing vocabulary uncommon for children his age. This demeanor stems from trauma forcing him to prematurely abandon childhood. He resents being underestimated due to his age or size, yet retains childlike traits. He secretly enjoys the children's show Featherman R and collects its merchandise, and exhibits naivety, such as believing Junpei Iori's deceptive claims about girls' attire. He dislikes milk but drinks it hoping to grow taller, despite apparent lactose intolerance causing discomfort. He deeply admires Akihiko Sanada's boxing prowess, addressing him respectfully as "Sanada-san". In combat, Ken wields a long spear to offset his small stature, ensuring he can engage adversaries on equal footing. His initial Persona, Nemesis – named after the Greek goddess of retribution – reflects his vengeful drive. During the October full moon mission, coinciding with the anniversary of his mother's death, Ken lures Shinjiro to the incident site and confronts him, intending murder-suicide. Takaya Sakaki intervenes, revealing Shinjiro's terminal condition from Persona-suppressing drugs and declaring Ken's revenge "pointless". When Takaya shoots at Ken, Shinjiro sacrifices himself by taking the bullet. With his dying words, Shinjiro urges Ken to live for his own future, shattering Ken's vengeful purpose. This loss plunges Ken into guilt and depression, causing him to flee the dormitory. He grapples with Shinjiro's admonition that living is harder than dying, feeling responsible for both deaths. Akihiko confronts him, delivering a blunt ultimatum to accept his mother's death. Ken realizes his quest for vengeance was an avoidance mechanism for his grief and loneliness. Choosing to live on for his mother and Shinjiro, he evolves his Persona into Kala-Nemi, a Vedic deity associated with time's cyclical nature, symbolizing his resolution to move forward. In later appearances, such as *Persona 4 Arena Ultimax*, Ken is depicted at age thirteen or fourteen as a Gekkoukan Middle School student and student council member. He shares a home with Koromaru, treating the dog like a younger sibling, and serves as a reserve member of the Shadow Operatives. His design reflects maturity – he wears a standard uniform, a wristwatch, and a student council armband, having outgrown his childhood orange jacket, now worn by Koromaru.