Juujunseiki Kantai, known as 重巡棲姫 艦隊 in Japanese, is a formidable Abyssal Fleet boss character in the Kantai Collection (KanColle) series. She represents the 'Heavy Cruiser Princess,' embodying the theme of a dark and powerful warship. As an enemy boss, Juujunseiki is memorable for her imposing design, high combat abilities, and challenging mechanics. She stands as a significant obstacle for players, symbolizing the strength and mystery of the Abyssal Fleet, and plays a crucial role in major event operations within the game.