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. *Note: Includes 2 extra chapters.*

The next school is the ''devil's school"! The main character, Morioka Yuto, who is oppressed for the reason of being a human being, bets the seat of the next Demon King and fights against the strongest demons! However, Yuto had a reason to be selected as a candidate ......! ?

To demons, humans are nothing but slaves. Morioka Yuuto, an ordinary high school boy, is selected as a candidate to be the next demon king. He is admitted into Ginsei Academy, a school for demons where he's scorned upon by the other students. "...I'll make you the demon king. So... make me your kin." After meeting Himekami Rizeru, a beautiful demon girl, Yuuto's world begins to change.

Kakeru Meguri is a second-year student at Minami Myojin Public High School who plays the character named in the VRMMORPG <\>. One day a player suddenly appears in front of his eyes, which turns out to be his popular beauty classmate Ririko Asagiri. She believes that if they defeat the demon king they will be able to return to the real world, in fact, Kakeru knows that if a player dies in the game, their consciousness will disappear in the real world. To save an important person, Kakeru possesses the most powerful awaken forbidden force, "Adult Mode". *Note: Ecstas Online was discontinued due to the death of Kakashi Oniyazu on February 2, 2019.*

The world will go to ruins if i stay together with her. But still, i'm in love with her-- Haruto, a commoner magician attending the magic academy, has confessed to princess Iris from a opposing country and ends up dating her!? But as it turns out, she is sharing her body with the demon king, and the world will come to an end if she is together with Haruto-- For her sake, he will get rid of her responsibilities and will destroy the curse! (Source: Fantasia Bunko)

This is a story of girls living their youth to the fullest! When Reina transferred from Hokkaido to Tokyo, what she wanted to do... was to be play DJ in the school's electronic music club! She dreams of spending her days in the electronic music club with like-minded classmates, but it seems that the club is not so popular at her new school, Sotokanda Bungei High School......? In a near-future Tokyo, girls engage in DJ battles! A story spun by music begins now... (Source: Ichijin Plus, translated)