Shota's Isekai NTR Adventure - Chapter 8 Rumours

Chang An, capital of Tang, the most powerful empire in the continent. A heaven wrecking massacre shook the city to its core. Amidst the incident, a young boy named Ning Que managed to get away, dug out from a pile of corpses along with a little girl called Sang Sang. Years passed, and since that day the two of them lived together. Together with Sang Sang they both entered the military, with plausible military achievements, they were recommended into the Scholar School, which began their miraculous journey.

After breaking up with his girlfriend, he accidentally acquired a genius system and rose from there against the heavens, becoming invincible..

- Description from Novelupdates

After being kicked out by her family, she turned out the real heiress worth billions, and people around her got to know it.Her family regretted deeply and demanded half of her fortune as repayment for bringing her up. She sneered and used a truth-telling talisman to expose their plots.A scumbag had always been pestering her and wanted to get back together. She easily made him “meet his ancestors” every night.Moreover, her cousins had looked down on her, regarding her as a disgrace.Surprisingly, the chairman of a rich family came to her and said, “As long as you can save my daughter, I'll meet all your demands!”Another rich family, who had been at feud with her new family for a long time, also shamelessly came over and said, “As long as you can help us, our family will be very grateful for the kindness of your family!”Later, even the rebellious cousin became her follower, claiming, “She is my only sister! Whoever dares to insult her, I will curse their entire family!”Her new family finally realized that their little poor girl was actually a big shot!“I need to draw spells, get rid of evils, save people and chase that guy! How busy I am!” She said in distress.That guy, “Actually, you don't need to chase me. I'm already yours.”

A young man with an extraordinary mind is off on an exciting adventure when he mysteriously wakes up in the body of a feeble slave-guy in a different, rich in quirks world.

The main character, a selfish jerk, would use extreme means to achieve his goals. However, he never allows his base instincts to overrule his sense of decency. He always pays back both good and bad deeds.

Will his (terrible/excellent) mentality help him make a fresh start? Will he get through misfortunes and hardships of the new world?