My Pet Beast is Super Fearsome - Chapter 621 - 620: Yamata no Orochi, Nine-Tailed

The NPC sets out on a journey to defeat the Demon Lord, joined by beautiful girls he meets along the way.---This is an NSFW story, so if you're under 18, turn back now, son. No NTR, and no full-on Yuri. There might be slight Yuri—like girls kissing and stuff during threesomes—but it's not that kind of Yuri where the girls fall in love with each other while in a relationship with the MC.---

“Players are welcome to board the special train for the Dimension Crack game. This train will go from the E-level departure station to the D-level station. Please ensure that your life is safe and orderly get on the train and abide by the rules of the ride.”

“Ride rules are as follows:”

“1. Please do not bring non-game items on the train. (Except underwear)”

“2. Must consume. (The train staff are all working without pay)”

“3. Do not turn on the lights after turning off the lights. (Except for those who are daring and talented)”

“In addition, the train encourages a variety of leisure methods such as sneak attacks, fights, and hunting. Players are invited to choose at will.”

“I wish you a pleasant journey.”

- Description from novelbuddy

Nijigen is a freshman and Banri’s friend. He gains his nickname at the tea ceremony club’s welcoming party after declaring his despair of the three-dimensional world and that he would live for the two-dimensional world from then on. His nickname in high school was “Satoutaka”.

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.

- Description from Novelupdates