Takumi Tsuzuki is a high school student who attends the Umenomori Private Academy, free of charge, alongside Fumino Serizawa, a childhood friend of his whom always says the opposite of what she feels. He spends most of his time at school fending off Chise Umenomori, the granddaughter of the board chairman and a pampered princess, who is constantly roping him into her eccentric hobbies. After school, he goes to work at the "Stray Cats" confectionery, a cake shop run by his adoptive older sister, Otome Tsuzuki, until it's time to go to bed. This is the average routine in the day and the life of Takumi. Mayoi Neko Overrun follows another seemingly average day in the life of Takumi. With his sister away from the shop, having gone to save someone else in need of help, Fumino takes it upon herself to wake him up so that he won't be late for their usual walk to school together, giving him a glimpse of her blue and white striped panties in the process. What a nice way to start the day. When Otome returns home, she brings with her a girl named Nozomi Kiriya, whose hair and mannerisms resemble that of a large cat. It turns out that she is a runaway that Otome can't help but take in. Takumi's ordinary days are transformed into splendid chaos as he tries to unravel who this mysterious beauty is and what she's running away from...

This anime is based on a playstation game under the same title. The story is about four people who travel the desolated land of Filgaea and carve themselves a legendary story while they're at it. These adventurers are Sheyenne Rainstorm, a gunslinger who holds the legendary weapon called ARMs; Kiel Aromax, a scientist who looks like he should be carrying a sword; Roleta Oratorio the Crest Sorceress, a magic-user who uses cards called Crests to cast spells; and Mirabelle Graceland, one of the Noble Red, which are a family of vampiric creatures who live alongside human beings They also travel with cute little intelligent furry things, from the Popepi Pipepo Tribe, named Isaac and Jerusha. (Source: AniDB)

One year ago, Sagiri Izumi became step-siblings with Masamune Izumi. But the sudden death of their parents tears their new family apart, resulting in Sagiri becoming a shut-in which cut her off from her brother and society. While caring for what's left of his family, Masamune earns a living as a published light novel author with one small problem: he's never actually met his acclaimed illustrator, Eromanga-sensei, infamous for drawing the most lewd erotica. Through an embarrassing chain of events, he learns that his very own little sister was his partner the whole time! As new characters and challenges appear, Masamune and Sagiri must now face the light novel industry together. Eromanga-Sensei follows the development of their relationship and their struggle to become successful; and as Sagiri slowly grows out of her shell, just how long will she be able to hide her true persona from the rest of the world? [Written by MAL Rewrite]

Sally, the kind but mischievous princess of the Land of Magic, has developed an interest in the human world. Wanting to experience it for herself, she runs away and meets two girls her age—Yoshiko "Yocchan" Hanamura and Sumire Kasugano—at a department store. They quickly become friends and spend time at Sally's mansion, which she conjured with magic. The two girls realize they forgot something at the store, and despite it having closed for the night, they leave to fetch the item. Sally and her younger brother Cub, who had been sent by their parents to retrieve her, follow them and discover that they have been captured by a pair of thieves who were attempting to rob the store. Utilizing their magic, Sally and Cub drive the thieves away and rescue the girls, who remain unaware of Sally's powers. Attached to her new friends and the fun of the human world, Sally decides to stay, taking up the surname Yumeno and attending school with Yocchan and Sumire. Cub chooses to live with her and together they make a variety of new friends and go on various adventures, all the while spicing up their lives with magic. [Written by MAL Rewrite]