A gamer is magically summoned into a parallel universe, where he is chosen as one of four heroes destined to save the world from its prophesied doom.

In a flooded world, a boy rescues a robotic girl from the sea. Grateful, she vows to be his "leg" until fulfilling her former master's order, leading to an unforgettable summer adventure.

At a high school full of unique characters, Tadano helps his shy and unsociable classmate Komi reach her goal of making friends with 100 people.

Ousai Academy was originally an all-girls high school. Due to the declining birth rates in recent years, it was converted into a co-ed school. The first year male students would find themselves surrounded by girls and unfortunately, Tsuda Takatoshi is one of them. What's worse, he gets scolded on his first day by the student council president Shino Amakusa, which did not give a good first impression of him. Tsuda also meets the other student council members while getting scolded, and in the end, he gets late for class. As an apology for ruining his morning, Shino lets him join the student council for various of "reasons" and he accepts it, or rather, he's forced to accept. Thus begins his days as Tsuda soon realizes that he's the only normal student in Ousai Academy...

Staz is a vampire from the surreal "Demon World", and Fuyumi, an ordinary girl, accidentally wanders into the Demon World through a portal. Subsequently after meeting each other, Fuyumi is killed by a carnivorous plant and turned into a ghost, causing Staz to take responsibility and pledge to help bring her back to life.