Iori Kitahara moves to the coastal town of Izu for his freshman year at its university, taking residence above Grand Blue, his uncle's scuba diving shop. Iori has high hopes and dreams about having the ideal college experience, but when he enters the shop he is sucked into the alcoholic activities of the carefree members of the Diving Club who frequent the place. Persuaded by upperclassmen Shinji Tokita and Ryuujirou Kotobuki, Iori reluctantly joins their bizarre party. His cousin Chisa Kotegawa later walks in and catches him in the act, earning Iori her utter disdain. Based on Kenji Inoue and Kimitake Yoshioka's popular comedy manga, Grand Blue follows Iori's misadventures with his eccentric new friends as he strives to realize his ideal college dream, while also learning how to scuba dive. [Written by MAL Rewrite]

Ittoki Sakuraba fails to understand why his mother, his uncle, and his childhood friend, Kousetsu, seem to take his security so seriously. Kousetsu constantly follows and observes him with no regard for his privacy, focusing only on keeping him safe every waking moment. But the consistent hounding starts making sense when an adorable second-year student at his high school, Satomi Tsubaki, asks Ittoki out on a date. Though initially innocent, Tsubaki's true intentions soon become apparent when Ittoki visits her house; she plans to assassinate him, and she is not alone. Surprisingly, the ones who come to his aid are his uncle and Kousetsu—donning their dark and deadly ninja attire. After Ittoki is escorted to safety, his mother reveals the truth: he is the 19th heir to a noble clan of ninjas known as the Iga, and the target of assassination by their rival clan, the Koga. In order to protect himself against this new threat, Ittoki must hone his skills at the only ninja academy remaining in Japan: the Kokuten Ninja Academy.

A man with a passion for vending machines awakens to realize that he has not only died, but he has also been reborn as one of his beloved machines! Although he is a modern appliance in a fantasy world, he requires money in order to keep functioning. He is stuck in one location until a young girl named Lammis stumbles upon him. Amazed by the drinks and food he sells, Lammis uses her "Blessing of Might" to lift him with ease and take him back to the village of Clearflow Lake. There, she officially dubs him Boxxo. Despite his inability to converse with the villagers, Boxxo becomes an essential part of the community. His goods provide nourishment, and, as he gains new abilities and products, he becomes a staple of daily life. Nobody is as loyal to Boxxo as his first and best customer, Lammis. The more time he spends with her, the more he tries to help her elevate her skills as a young hunter.

The "Noblesse" Cadis Etrama di Raizel, also known as "Rai," is enrolled in Ye Ran High School by his servant Frankenstein to stay hidden from the sights of the Union, a mysterious organization out for Rai's blood. Rai commences his life as a student, making himself familiar with his classmates and the daily activities of humans. However, his new life is far from peaceful, and Rai is soon forced to save his new friends from the hands of the Union that had abducted them. Meanwhile, M-21—a Union agent gone rogue during Rai's rescue operation—joins the Ye Ran High School security staff after a proposition by the school's director, who happens to be none other than Frankenstein himself. On the surface, M-21 is a prim and proper employee, but in truth he is shackled by his former ties to the Union and the inevitable consequences of betraying the organization. To further complicate matters, Nobles Regis K. Landegre and Seira J. Loyard enroll in the same school to investigate the Noblesse. While the Union conducts a manhunt for M-21 to extract clues regarding their missing agents, Rai is forced to keep his identity hidden while protecting all that he holds dear. [Written by MAL Rewrite]