Qiubai has traveled to a world where inner and outer worlds merge. Growing up, he's surrounded by characters he's "familiar" with. There's Akizuki Airi, Akizuki Marina, Shiina Chizuru, Mashiro Chisato, Hoshizuki Kaede, Hoshizuki Suzu, Nanao Akane... and his two younger sisters, Mikan Yuuki and Kasugano Sora, who live with him. Mikan is young, but capable, mature, and energetic, taking care of the housework daily, making her a worry-free existence. Sora is slightly older, but aloof and tsundere, with a slightly frail constitution. She stays at home every day, a worrying prospect. When Qiubai turns 18, the system officially activates! Kuze Akibai: What? Just coming of age, I have to become a male succubus in the inner and outer worlds? And I even have the ability to stop time!

Traveling to the world of Demon High School, Vitan Asmodeus met the legendary magic book Radix Astyr.

Embarking on a journey through the dimensional world!

In the world of the mechanical girl, mastered the seventy-two pillars of the devil, understood Sloth, and became the devil body Berial.

In the dark bullet world, judged the ignorant and selfish humans, understood Pride, and became the devil Lucifer.

In the world of the date, controlled the Kabbalah Tree of Life, understood lust, and became the devil Asmodeus.

In the sword dance of the elves, swallowed the world, understood gluttony, and became the devil Beelzebub...

In

the box garden, the great devil of the final trial of mankind, Vitan Asmodeus, looked at the many beautiful women in his community and couldn't help being silent!

Why do I have so many harems!