Looking at middle school student Rentarou Aijou, you might easily think he's the very definition of bad luck: one hundred girls have already rejected him, and it definitely doesn't seem like his streak of bad luck will ever end. With his willpower to find a girlfriend slowly but surely waning, he decides to resort to what appears to be his last resort: he visits a shrine and pours his heart out to the gods and goddesses, hoping to find divine assistance in his search for a suitable—or any—life partner. As fate would have it, a deity happens to be present who wants to help the grieving boy. She promises him that in the near future, he will meet not just one, but a whole hundred soulmates.

Rentaro Aijo was rejected 100 times in middle school. He visits a shrine and prays for better luck in high school. The God of Love appears and promises that he'll soon meet 100 people he's destined to date. But there's a catch—once destiny introduces someone to him, the two must happily love each other. If they don't, they'll die. What will befall Rentaro and his 100 girlfriends in high school?

アニメ「かくしごと」はマンガ家であることを娘に内緒にしている後藤可久士と、娘・姫の日常をつづるコメディ。原作者・久米田康治の画業30周年を記念した劇場編集版では、新規カットが追加され、テレビアニメとは異なるもう1つのラストが紡がれる。

Rentaro Aijo was rejected 100 times in middle school. He visits a shrine and prays for better luck in high school. The God of Love appears and promises that he'll soon meet 100 people he's destined to date. But there's a catch—once destiny introduces someone to him, the two must happily love each other. If they don't, they'll die. What will befall Rentaro and his 100 girlfriends in high school?

Unaired special of “Himouto! Umaru-chan” included with the manga’s seventh compiled volume. After being tempted by a pillow on the television shopping channel, Umaru has a dream reminding her to appreciate the pillow she has. The next day, Umaru goes with Sylphnford to the convenience store where she tries to win a lottery prize. Later, Umaru and Taihei go wild at a yakiniku restaurant, unaware that Nana is at the next table over. At the start of October, Umaru and Kirie get into the Halloween spirit early, dressing up in costume and trying various pumpkin-based snacks. Afterwards, Umaru decides to fake a fever in order to skip school, only to be overcome by guilt.

The year is 1939 - it was then that the Neuroi appeared. Nobody knows where they came from or what their ultimate agenda is, but the fact remains that their attacks drove people out of their towns and cities. In order to take arms against them, humanity develops a new anti-Neuroi weapon called the "Striker Unit." Using the power of magic to fight against the monsters, this new device enhances and amplifies the power of female magic-wielders. To use this device, young witches from all over the world have been brought together to form an elite task force unit called the 501st Joint Fighter Wing, commonly known as the "Strike Witches."

After disbanding, the girls of the 501st Joint Fighter Wing return to face the threat of the Neuroi again, now joined by a new member, Shizuka Hattori.