With the seas under constant threat from the hostile "Abyssal Fleet," a specialized naval base is established to counter them. Rather than standard naval weaponry, however, the base is armed with "Kanmusu"—girls who harbor the spirits of Japanese warships—possessing the ability to don weaponized gear that allows them to harness the powerful souls within themselves. Fubuki, a young Destroyer-type Kanmusu, joins the base as a new recruit; unfortunately for her, despite her inexperience and timid nature, she is assigned to the famous Third Torpedo Squadron and quickly thrust into the heat of battle. When she is rescued from near annihilation, the rookie warship resolves to become as strong as the one who saved her. [Written by MAL Rewrite]

Eighteen-year-old Dale Reki is a skilled, kind, and respected traveller, acknowledged as one of the leading adventurers in the city of Kreuz. One day while on the hunt for magical beasts, he comes across a sweet devil girl named Latina. She is alone, dressed in rags, and bears the devils' symbol of a criminal: a broken horn. Concerned for her wellbeing, Dale decides to ensure Latina's safety by bringing her to his home, eventually leading to him adopting her. Latina is sweet, innocent and compassionate, charming Dale beyond his expectations. He begins to enjoy the life of parenthood— experiencing the trials that come with raising a child and coping with the heartache he feels whenever his busy lifestyle as an adventurer parts him from her. Although work and life as a new parent become reassuring constants for Dale, the mysteries surrounding the girl remain. Why was Latina alone in the forest, and why does she harbor the symbol of a criminal? At the same time, Latina also begins to learn about the world and herself as she adjusts to her new life with Dale. [Written by MAL Rewrite]

The infidelity of Eita Kidou's parents not only made his family fall apart, but also made him skeptic of love. Having no intention to delve into romance, Eita devotes his entire high school life to his studies in order to become a doctor. It did not take long for the beautiful and popular Masuzu Natsukawa to notice Eita's apathy. Tired of being the object of people's affection, she asks him to pretend to be her boyfriend, as she too feels disgusted at the notion of love. Eita, however, refuses—yet Masuzu has one trick left up her sleeve: Eita’s journal and threatening to post the embarrassing content online if he does not comply. Now entangled in a fake romance with the most desired girl at school, Eita's life is turned upside down. Whether envied by his peers or receiving a confession, he must cope with his newfound relationship and all the troubles that come along with it. [Written by MAL Rewrite]

On his way home from school, Tatsumi sees a man collapsed near a lake. When he approaches him, Tatsumi notices something strange: the person in need of help is actually a beautiful merman named Wakasa! Because Wakasa's home has become too polluted to live in, Tatsumi graciously offers his bathtub as a refuge. With a boisterous merman as his new roommate, Tatsumi's normal life won't be returning anytime soon, not to mention Wakasa's aquatic friends—Takasu, Mikuni, and Maki—often show up uninvited, making them all quite a handful for the high school student. As he humors their curiosity for human life, Tatsumi sometimes finds himself enjoying their childish antics, but he will have to keep his cool if he intends to keep up with his daily life and newfound friendship. [Written by MAL Rewrite]