Spiral Zone (1987)

Nobunaga was a teacher who was waiting for that kind of dating sim event to happen in real life. One day, a 14 year old girl named Kicho appears in front of him, saying that she's his wife?! Apparently she came from the Warring States era and seems to have mistaken Nobunaga for the Oda Nobunaga and tells him that she wants to have his children. An age-gap love comedy featuring a teacher with a dating sims brain and a princess with a warring states era brain!!

After having descended upon this world, the gods have created guilds where adventurers can test their mettle. These guilds, known as "familia," grant adventurers the chance to explore, gather, hunt, or simply enjoy themselves. The Sword Princess, Ais Wallenstein, and the novice mage, Lefiya Viridis, are members of the Loki Familia, who are experts at monster hunting. With the rest of their group, they journey to the tower of Babel in hopes of exploring the dungeon underneath. Home to powerful monsters, the dungeon will fulfill Ais's desire to master her sword skills, while bringing Lefiya closer to her dream of succeeding Riveria Ljos Alf, vice-captain of the Loki Familia, as the most powerful mage in the land.

At the end of her first year of high school, Futaba Yoshioka suddenly has a chance encounter with her first love, Kou Tanaka. Three years ago, he transferred schools before she was able to say how she felt about him. After meeting each other again, Futaba realizes that he has gone through many changes. He acts more cool and even had his last name changed to Mabuchi. Gradually the two rekindle their love while piecing together what had happened in the time that they were apart.

Yui Hirasawa has no clue which club to join, but she’s determined to do something this year. As luck would have it, she discovers a flyer for the Light Music Club and decides this is the club for her. But there's one problem: She first must learn guitar!

Natsuo is a high school boy who is experiencing the crushing despair of unrequited love. To make matters worse, the person he is in love with is his teacher, Hina. In an attempt to lift his spirits, he attends a mixer where he meets a girl named Rui. The two sleep together, expecting never to see one another again, but fate has other plans. His life suddenly becomes more complicated when his father comes home and announces he has remarried a woman with two daughters whom Natsuo has met before: Hina and Rui!

Our MC finds out that his school requires him to join a club and during his reluctant search he stumbles upon Tejina-senpai attempting magic tricks in her clubroom. Tejina-senpai has massive stage fright however and so now that she has an audience her attempts are simply comedic.

A door to another world stretches out before a boy who's been brutally bullied all his life. This alternate reality grants him access to all sorts of things, like cheat skills and a portal that lets him travel between his old and new worlds! Can this class loser turn his life around back home...?

Posing as her twin brother in a boy band, a young woman wins the heart of her bandmates and fans, all the while searching for her long-lost mother.

Killing Goods are murder weapons handed down from generation to generation within the families of their owners. They are cursed to compel their current owners to repeat the original murders. The curse also makes them indestructible. Kiri Haimura is the current owner of a pair of shears that can cut seemingly anything, although the only thing he wants to cut is hair. One day he meets Iwai Mushanokoji, a girl of whom he has only heard rumors that her hair cannot be cut, a girl who can grant one wish, any wish, but only to the person who murders her. Every morning he cuts her hair, which grows back every night; and every day he helps protect her from people who know about her curse and who want a wish granted.

Hida Kizuna possesses the HHG (Heart Hybrid Gear) ability, but it is not strong enough to make him particularly important. His older sister calls him to transfer to a strategic defense school, where many of the students (many of which are large-breasted girls) use their HHG abilities to fight invaders from another world while wearing extremely skimpy pilot outfits. Kizuna's fighting ability doesn't measure up, but his sister has another plan—apparently having erotic experiences with Kizuna will allow the girls to replenish their energy or power-up. It looks like his new school life is going to be full of embarrassment.