Netherworld Investigator - Chapter 449

The queen’s essential feature is this: [must be a woman or a feminine-looking man].

The previous life is nothing but a joke. Being used completely then abandoned mercilessly. How can I be this stupid to not even notice such an obvious scam? Fortunately, I can have a second chance with my rebirth. Sister, Brother Yi and whoever mistreated me in my previous life, are you ready for my revenge and the counterattack of a princess?

In the rebirth, in order to prevent the tragedy of the previous life from happening, Bai Yu decided to rush to the [Tower of God] at any cost, and face everything together with his sister!

However, Bai Yu, who was bound by the system, mutated his bloodline, and transformed into a black-scaled python seems to be developing on a completely different path from his previous life…

- Description from novelbuddy

Qin Tian accidentally transmigrated into a sickly body, a body with broken Dantian that was unable to practice Qigong, in another world. Fortunately, God had mercy on him by giving him a level up system. Useless? That was him in the past. Not worrying about practicing Qigong, he was now able to kill Monsters to level up. Easy! Level up when killing Monsters; level up when killing people. An unbeatable sovereign of the clan in the eyes of other people, but in his eyes, he is a glittering big BOSS.