Mitsuru Kirijo bears the weight of her legacy as heiress to the powerful Kirijo Group. Her family, particularly her grandfather Kouetsu Kirijo, conducted experiments that accidentally birthed the Dark Hour and Shadows. This history compels her to lead the Specialized Extracurricular Execution Squad (SEES) against these threats, seeking atonement. As a third-year Gekkoukan High School valedictorian and student council president, her sheltered upbringing within the Kirijo Group left her inexperienced with common activities and casual social norms. She initially addresses SEES members formally by last names, gradually shifting to first-name terms with closer allies like Yukari Takeba. Within SEES, Mitsuru first serves as navigator during Shadow operations, using her Persona, Penthesilea, for tactical support. When Fuuka Yamagishi joins with superior analytical abilities, Mitsuru transitions to frontline combat. Penthesilea employs ice-based attacks and rapier fencing, leaving Mitsuru vulnerable to fire. Following a personal awakening through grief, her Persona evolves into Artemisia, enhancing her ice and healing capabilities. Mitsuru initially concealed the Dark Hour's origins from SEES, burdened by shame. Her resolve shatters when the trusted advisor Shuji Ikutsuki murders her father, Takeharu Kirijo, triggering an existential crisis. Yukari Takeba's intervention helps Mitsuru refocus on honoring her father's legacy, catalyzing her Persona's evolution and strengthening their bond. During SEES's Yakushima trip in *Midsummer Knight's Dream*, her father reveals the Kirijo Group's time-manipulation experiments and their link to Yukari's father, Eiichiro Takeba. Mitsuru supports Yukari through the turmoil and later oversees the integration of new members Aigis and Ken Amada. Beyond the film, Mitsuru graduates to lead the covert Shadow Operatives, addressing Shadow-related incidents. In *Persona 4 Arena*, set two years after *Persona 3*, she confronts Kirijo Group experiment remnants while navigating leadership challenges. Her commitment extends to personal sacrifices, like vowing unconditional support for Yukari after the protagonist's death. Beneath her composed exterior, Mitsuru harbors a hidden enjoyment of combat, occasionally mirroring Akihiko Sanada's recklessness in battle, and displays awkwardness in casual settings. Her social links reveal insecurities about her prescribed future, including contemplation of abandoning an arranged engagement.