Ume Kurumizawa, preferring the nickname Kurumi, masks a calculating nature beneath a charming, popular exterior. Her fixation on Shouta Kazehaya originates from their middle school days, when his kindness during a脆弱 moment ignited an enduring infatuation. Threatened by Sawako Kuronuma’s closeness to Kazehaya, Kurumi weaponizes false rumors under Sawako’s name, targeting her friends to isolate her—a tactic born from prior betrayals where peers exploited her social standing for romantic gain, cementing her distrust and defensive posturing. Kazehaya’s rejection of her confession shatters her manipulative patterns, compelling a shift toward candor. Observing Sawako’s persistent compassion despite her own malice, Kurumi’s rivalry mellows into respect. Haunted by remorse, she atones by aiding Sawako against tormentors, catalyzing a fragile alliance. Adulthood sees Kurumi and Sawako collaborating as educators, their partnership deepening into trust. Initial clashes with Sawako’s cousin, Eiji Akahoshi, evolve into romance as Kurumi confronts lingering self-doubt, learning to embrace his earnest devotion. Her trajectory—from envy-fueled deceit to accountability—peaks in reconciling with former victims and nurturing sincere relationships. Pivotal struggles include confronting her own toxicity while laboring to change, and prioritizing her platonic bond with Sawako over unrequited feelings. Tensions with Ayane Yano reveal a nuanced push-pull of rivalry and kinship, each mirroring the other’s guardedness. Her given name, Ume (“plum”), evokes spring’s renewal and spiritual safeguarding, juxtaposed with Kurumi (“walnut”)—a metaphor for her brittle shell softening through growth. The narrative closes on her academic and emotional evolution, underscoring redemption through persistent self-reflection and repaired connections.