MTL - My Inseparable House Guests - Chapter 36 Gray is the main color

An Individual from Earth finds themselves in the Shinobi World, equipped with a Scientific System. From that moment, he delved into scientific research far ahead of its time.

Have you ever wondered what it would feel like if your dick exploded? Or if voodoo or black magic actually worked?Axel got a crash course in both after leaving a one-star review for a trashy smut novel where the hapless author-san offed a minor villain. Little did he know that this particular author had some serious power.Suddenly, Axel found himself in the body of the very villain he was lamenting, right at the moment when everything was about to spiral into chaos.Now, with a second chance at life (and a brand-new set of problems), Axel must navigate the wild world of villainy—complete with explosive consequences and dark magic—if he wants to rewrite his story before it ends in disaster.

In his past incarnation, Lu Xuan was the youngest Celestial Lord that the universe has ever seen!
An accidental rebirth brought him back to a thousand years before, where the Earth had just begun its spiritual reawakening. When he stepped onto the way of cultivation for a second time, he swore to rewrite all injustices suffered in his past life, and defeat all enemies that dare stand in his way!
Let invincibility be his cultivation and the path he treads. In this life, it is his destiny to be invincible!

There exists eight hardships of human life- living, aging, being sick, dying, resenting, parting with loved ones, being unable to let go, and being unable obtain something.

In each life, each person will experience their own hardship. Once they obtain happiness, they are furthermore unable to let go. Whether it would be heartfelt love or resenting someone down to the bone, would it matter? As long as that person’s bone has my name, it would be good.

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