Haruna
She's a Fog battleship—basically a sentient warship from the mysterious fog that covers the oceans. Her human form is a teenage girl bundled up in a heavy coat that covers everything but her face, which fits her whole "fog" aesthetic. She's the anthropomorphic avatar of the fourth Kongou-class battlecruiser, which is where her name comes from.
Haruna's whole character arc kicks off when she tries to take down I-401 and fails. Instead of staying loyal to the Fog collective, she ends up befriending a girl named Makie and decides to protect her—even if that means going rogue against her own kind. It's a pretty significant shift from her initial mission, and it shows her capacity to care about individuals over orders.
Makie calls her "Haru-Haru," which is the kind of casual nickname that shows how close they've become. Despite being a massive warship at her core, Haruna's willing to stand against the entire Fog to keep Makie safe, which is kind of her defining trait.
Content compiled by AnimeList.moe from publicly available sources.
