Ken Amada is the youngest human member of SEES, and one of the two who don't attend Gekkoukan High School. He is mature, but sometimes he is too precocious for his own good. He uses long spears to make up for his short stature. His Personas can be used for healing, and to cast light-based spells that occasionally instantly kill the enemy. Ken is invited by Ikutsuki to live in the SEES dorm because he is an orphan with no home to return to. He is revealed to have the potential to wield Persona and is asked to join the organization. Initially, the Main Character and his friends believe that Ken joined SEES out of altruism, but his true intentions are far darker. Ken's mother was accidentally killed by Shinjiro during a SEES mission, and Ken infiltrates SEES in order to kill him. During Ken's confrontation with Shinjiro, Takaya intervenes and reveals that Ken has been planning to commit suicide after killing Shinjiro. He also reveals that Strega has been supplying Shinjiro with special drugs to control his Persona, and that the drugs will soon kill him. This completely shatters Ken’s hopes of revenge. After a brief fight between Shinjiro and Takaya, the Strega leader takes a shot at Ken. Shinjiro jumps in front of the bullet. Dying, he reminds Ken that he is still a child with a whole life ahead of him and a future that can be about more than vengeance. Shinjiro's last words inspire Ken to fight for the future his mother would have wanted for him. According to character designer Shigenori Soejima, Ken was designed to have a nostalgic look, rather than to reflect the style of modern Japanese children.
Koromaru's master was killed in an incident involving Shadows. He became a stray, and was watched over by Fuuka and Yukari. Instead of attacking with his fangs or claws, Koromaru wields daggers in his mouth. His Personas can be used to cast fire spells, as well as darkness-based spells that occasionally instantly kill the enemy. He has a speed advantage over the other characters. Koromaru remains faithful to his master even after his death, retracing the path of their old walks and revisiting the place where he was slain. One day when Akihiko is hunting Shadows, he comes across the canine, who is gravely injured. The Shadows surrounding him are dead. Once Koromaru is healed, Ikutsuki reveals that he too has the potential to summon a Persona. Mitsuru gives him a special collar-like Evoker and he is inducted into SEES. Aigis claims to be able to translate Koromaru's barking and body language into human speech.
Initially, Ikutsuki appears as the cheerful advisor, chairman, and "boss" of SEES, always trying to keep the group in high spirits while discovering secrets about the Shadows. In truth, Ikutsuki is working toward a completely opposite end, sharing Mitsuru's grandfather's dream of The Fall and the coming of Nyx. He was one of the scientists involved in the experiments at Gekkoukan ten years ago, including the creation of artificial Persona-users. Ikutsuki manipulates SEES to destroy the twelve Arcana Shadows, promising them that once they do so they will eliminate the Dark Hour. But killing the twelve Arcana Shadows actually melds them together, allowing for the re-emergence of the thirteenth Arcana, Death. It is Death's function to summon Nyx and destroy the world. After his lies are discovered, Ikutsuki reprograms Aigis to sacrifice the members of SEES as offerings for Nyx, and then kills Takeharu Kirijo. When Aigis breaks the programming and frees SEES, Ikutsuki jumps to his death from the top of Tartarus after being wounded in the stomach by a bullet. Unfortunately, his mission to revive Death was already complete by the time of his suicide.
An exchange student from France. He is the president of the Fashion Club. His arcana is Temperance.
The manager of the sports teams. She doesn't know what to do with her life until she helps a group of children improve their running skills. Yuko is one of the girls that the Main Character can romance. Her arcana is Strength.
A student who claims to be an expert on food. He has unresolved issues concerning his late brother. His arcana is the Moon.
Eiichiro Takeba is Yukari's father and one of the scientists working for the Kirijo Group during the Shadow Incident in 1999. The corporation blamed the accident on him even though he was trying to blow the whistle on their dangerous and unethical experiments. Eiichiro died while making a video for Yukari, which Ikutsuki later altered to manipulate SEES.