Hai-Furi, also known as High School Fleet, is an anime series that follows a group of high school girls training to become Blue Mermaids, a prestigious naval force. The story unfolds in a world where most of Earth's land is submerged, and sea navigation is vital. The anime explores themes of friendship, teamwork, and adventure as the girls navigate various challenges on their ship, Harekaze. The series combines elements of action and slice of life, providing a unique and engaging experience.