Miku Kohinata stands as a central figure throughout the *Symphogear* series and its extended media. She anchors Hibiki Tachibana emotionally as her childhood friend and dormitory roommate at Lydian Private Music Academy. Their deep bond forms Miku's core, marked by profound guilt over Hibiki's near-fatal injury at a Zwei Wing concert—Miku invited Hibiki but missed the event due to a schedule conflict, leaving Hibiki exposed to a Noise attack. This event forged Miku's intense protectiveness and occasional possessiveness towards Hibiki, alongside a lasting aversion to violence and secrets.

Initially portrayed as a civilian with pacifistic leanings, Miku's development accelerates when her emotional vulnerabilities are exploited. During *Symphogear G*, her desperate need to shield Hibiki enables synchronization with the Shénshòujìng relic, transforming her into a temporary Symphogear wielder. She uses this power to destroy the corrupted Gungnir relic endangering Hibiki, fully aware she risks mental manipulation from the relic's feedback. This act reveals her latent bravery despite her non-combatant nature. Her pacifism resurfaces in *Symphogear AXZ*, where witnessing graphic violence causes her to faint, though she later aids S.O.N.G. operations when necessary.

Miku's internal conflicts intensify in *Symphogear XV*. Her unresolved romantic feelings for Hibiki make her susceptible to possession by the goddess Shem-Ha Mephorash, who exploits Miku's yearning to confess her emotions, using her body as a vessel. After liberation, Miku immediately joins the final battle against the Yggdrasil System, demonstrating her commitment to protecting others despite her distaste for conflict. Her character arc culminates in an implied love confession to Hibiki in the series finale, with supplementary material like the mobile game *Symphogear XD Unlimited* confirming their romantic relationship in post-canon stories.

Her personality blends compassion with complexity. Empathetic and valuing honesty, Miku reacts negatively when Hibiki conceals her Symphogear activities. Flashbacks reveal a competitive past as a sprinter, where she viewed others as rivals; this arrogance faded after transferring to Lydian to prioritize companionship with Hibiki. She expresses unspoken emotions through piano playing and songwriting—solo tracks like "FOR THE FUTURE" and "Waikyō Shénshòujìng" explicitly reference her love for Hibiki. Symbolic gestures further underscore their relationship, including sharing a bed despite owning bunk beds and a Ferris wheel date scene implying a kiss.