Inazuma is the personification of the Japanese destroyer Inazuma, the fourth and final vessel of the Akatsuki-class destroyers, and is one of the five starter ships available to admirals at the beginning of the game. Her name means lightning, a fact that informs some of her nicknames, such as Den-chan, derived from an alternate reading of the kanji for lightning. Physically, she is depicted with long brown hair styled into a signature folded ponytail and wears the standard white and dark blue sailor uniform, or serafuku, of her class. A distinguishing feature is the Roman numeral for three, a pin that appears on the lower right side of her shirt, symbolizing her status as part of the third group of special-type destroyers.

Her personality is markedly shy, timid, and innocent, creating a direct contrast with the more outgoing nature of her sister ship, Ikazuchi. This gentle demeanor is best expressed through her well-known verbal tic, nanodesu, a soft and childlike phrase she attaches to the end of her sentences. This pacifistic and kind-hearted nature is not merely a character quirk but a direct reference to the historical actions of the original vessel. In one of her in-game quotes concerning night battles, she expresses a wish to save even sunken enemy ships if possible. This is a direct nod to the real Inazuma's rescue of over four hundred surviving crew members from the allied ships HMS Exeter and HMS Encounter after the Second Battle of the Java Sea, an act that is central to her motivation. While she understands the necessity of battle, her stated desire is to avoid fighting whenever possible, and she treasures moments of peace. She is also portrayed as somewhat clumsy, a trait derived from the historical ship's involvement in several collisions with other vessels, including the destroyer Miyuki. A notable fan-created divergence from her standard personality is the concept of Plasma-chan, a darker, more menacing persona that emerges in some interpretations, often triggered by severe stress or when she is pushed to her breaking point, where her catchphrase can become the more threatening nanoDEATH.

Within the context of the story and her role in the fleet, Inazuma serves as a reliable and dedicated member of the Sixth Destroyer Division, alongside her sisters, particularly Ikazuchi, with whom she shares a close bond. Her motivations are consistently peaceful; she fights because it is her duty, but her ultimate goal and the source of her internal conflict is reconciling her desire to protect life with the harsh realities of war. This is encapsulated perfectly in her MVP quote, where she questions whether it is strange to want to both win the war and save lives. In her interactions with the admiral, she is deferential and a little uncertain, often asking if she is being mistaken for someone else, and she expresses gratitude for quiet moments and small acts of kindness, such as offering the admiral a shoulder massage after a long day of work.

Her development as a character is subtle, rooted in her history. Unlike some characters who seek power or glory, Inazuma's growth is about maintaining her compassion in a difficult environment. Her remodel, Inazuma Kai, represents her becoming more capable and battle-ready, yet her core personality remains unchanged. Her notable abilities as a destroyer lie in her versatility and specialization. She is equipped for anti-submarine warfare, capable of carrying depth charges and sonar. She also possesses strong torpedo capabilities for powerful night attacks, a common trait for destroyers in her class. Her upgraded forms and specific equipment setups, such as surface radars and various torpedo mounts, can provide her with significant combat bonuses, allowing her to be an effective participant in fleet operations. Her primary strength, however, remains her unwavering, gentle spirit which, despite the horrors she has witnessed and her own wish for peace, continues to drive her to protect those in her care.