The Protagonist's Party is Too Diligent - Chapter 41

Luo Qiu became the boss of a ‘club’ by chance.

It was a weird club that sold strange items and with a servant girl that had 300 years of working experience. Countless people with dreams, hopes and ambitions came to the club to exchange anything precious they own for what they want. They would offer their lifespan, items, and even their soul. Every successful trade would increase Luo Qiu’s lifespan by a little.

“Tribute successful, your lifespan has increased by 99 years.”

As thus, Luo Qiu began his endless life as the club’s boss.

- Description from Novelupdates

My brother* and I, from elementary school to university, had grown up together. We didn’t just get into the same degree, we’re also sharing the same dormitory room.

The world is terrorized by the powerful Black Witch who has been sealed in the moon. Every ten years, the night of Hexennacht arrives and a chosen witch must battle the Black Witch in hopes of finally defeating her.

As the current decade’s Hexennacht approaches, a mysterious girl named Kagami Kagami arrives and meets Horinouchi Mitsuru, the daughter of the previous Hexennacht representative.

It takes place between Kyoukai Senjou no Horizon and the City Series, two other series by the author.