Crown of Thorns - Chapter 66

A girl who calls herself a demon appeared before a timid student named Fumio Kijima. The girl claims to be a campaign girl from the demon world and she gives him the ability to “summon a room” from nothing but thin air.

At first he doesn’t abuse his power and uses it as a convenient ability in his every day life. But one day he is bullied by his classmates under a false pretext and is made to suffer. In the past he would have wallowed in misery and cried himself to sleep, but now he had a power to call upon.

“I will make them regret it!”

Using his powers to summon his “room”, he begins his era of confinement and brainwashing to achieve his goals.

“There are no heroes. In life, the monsters win.”

...

In 2106, [Mayhem Online], a fully immersive VRMMO game, was released. Soon, it dominated the world's economy when people could exchange the in-game currency with real-life currency and vice versa.

In the year 2107, Flynn Grey, a 22-year-old college dropout with an ambiguous history, joined in the fray of billions of people that had already started playing [Mayhem]. Hoping to uncover the game's secret and earn a fortune, he spent months on adventures without fruitful results.

For better or worse, Shura, Flynn's in-game character, ends up in a great Wyvern's den, acquiring a hidden class and a monstrous race. Join him as he defeats his past and paves his way into becoming a true legend in both worlds.

[The Golden Snake Sword was successfully strengthened, and the Snake Queen was summoned. ]. ?Snake Queen: Master, please tell me what you want!

[The skill ‘Evil Light Ghost Slash’ was successfully strengthened, and after summoning the ghost ghost. ]. what! female ghost? Then I’ll put you on maternity leave!

[The Yao soul suit has been strengthened successfully! ]. Um? Is this the Yao princess? Princess Yaoyao! Don’t get on me!

Zhou Han was surprised to find that the only SSS-level talent in the universe that he had awakened: infinite enhancement, was so awesome.

- Description from novelbuddy

“I have to squander; otherwise, won’t it be a waste of my parent’s talent at earning money?” Hong Dali answers a reporter’s question matter-of-factly.

Just after the interview ends, Hong Dali opens the Great Prodigal System’s interface and looks at the various good stuff displayed in it. Stroking his chin, he mumbles to himself, “I just need to squander 200 billion yuan more to exchange for the blueprint of the core technology, Engine Destruction, found in the strongest humanoid mecha weapon, Neo Granzon. Looks like I’ll have to work harder!”

“I want to splurge! I want to squander!”