Eighteen-year-old Tsukasa Mizugaki has failed his college entrance exams, but after pulling some strings, he manages to land a job at the Sion Artificial Intelligence Corporation. SAI Corp is responsible for the creation of "Giftias"—highly advanced androids which are almost indiscernible from normal humans. However, unlike humans, Giftias have a maximum lifespan of 81,920 hours, or around nine years and four months. Terminal Service One, the station Tsukasa was assigned to, is responsible for collecting Giftias that have met their expiration date, before they lose their memories and become hostile. Promptly after joining Terminal Service One, Tsukasa is partnered with a beautiful Giftia named Isla. She is a Terminal Service veteran and considered the best in Giftia retrievals, contrary to her petite figure and placid nature. Time is fleeting though, and Tsukasa must come to terms with his feelings for Isla before her time is up. No matter how much someone desires it, nothing lasts forever. [Written by MAL Rewrite]

When aliens known as the Oni threaten to invade the Earth, they promise to leave under one condition—a randomly-chosen human must win a one-on-one game of tag against Lum, the beautiful daughter of the Oni leader. The "lucky" person selected happens to be the lustful and unlucky high schooler Ataru Moroboshi. Given 10 days to attempt to grab Lum's horns, Ataru realizes how impossible the challenge is as he is faced with Lum's extraterrestrial powers. Motivated by a promise of marriage from his childhood friend Shinobu Miyake, Ataru manages to catch Lum off guard. He mistakenly grabs hold of her bikini top first, but he eventually achieves his true goal. Although the game is over, Lum misunderstands that she is the one whom Ataru wants to marry, and she decides to move in with him. The poor student constantly tries to shake off the clingy Lum while doing his best to reconcile with his desired fiancée. After Ataru's heroic feat results in such a disastrous outcome, it is questionable whether luck will ever be on his side.

As far as it goes, many boys, especially in their teenage years, want to have a girlfriend. Keiki Kiryuu is no exception. One eventful afternoon, his days of yearning for a lover seem to come to an end when he receives a love letter from an anonymous sender—along with a pair of white panties. To determine the identity of his secret admirer, referred to as Cinderella, he proceeds to investigate several possible candidates including his senior Sayuki Tokihara, his underclassman Yuika Koga, and his classmate Mao Nanjou. However, as Keiki seeks to uncover who this mystery girl might be, he comes to know about the perverted fetishes hidden behind each candidate's innocent exteriors... [Written by MAL Rewrite]

"My senpai from work... is tiny and cute." Shinozaki is an office worker who is taken care of and coddled by his senior team member Shiori Katase: a gorgeous, profoundly kind, loving, and diminutive woman. Shinozaki certainly hopes that she's not doing it out of duty... but her joy of doing so increasingly exposes her feelings!