The Doctor Who Loves Me - Chapter 8: Doppelganger

One day, a mysterious tower suddenly appeared in the city. The people decided to call it a dungeon, and while it was full of rugged terrain and dangerous monsters, it was also a land of opportunity, where countless treasures awaited. When Sejun, a young man living an ordinary life, is invited to the dungeon by chance, he is thrilled at the prospect of becoming rich, but he is stranded in a hidden area of the mysterious tower. All he has is a few seeds and his body. Now Sejun must farm, collect resources, and figure out his own survival strategy!

In the winter of Taikang Year 3, a girl pays a visit to her future in-laws, the Ning Family of Beiliu, Yangcheng.

After her engagement was denied, the girl decided to hang herself in front of the Ning Family to show them her sincerity.

When the girl who had died opened her eyes once more, many people’s fates were changed forever.

- Description from Novelupdates

The day Louis discovered his girlfriend's betrayal, he died from a gunshot wound to the head. Fortunately, fate smiled on him and allowed him to be reincarnated in a magical world as the youngest son of an SSS-class family.That same day, he awakened his Class—an event that should have marked the beginning of his rise.Instead, it marked his downfall.[Ding! You have awakened an SSS-Rank Class.][Class: God of Money][Rank: SSS]A god? Yes, that's beautiful. But a god of money? In the eyes of his proud family, that title was a joke—an insult. The weakest, most useless Class imaginable.So, they banished him, stripped him of the family name, and cast him aside without a second thought.But they were unaware of his skill, abilities, and the potential that money could bring.He smiled as he saw himself banished and looked at the system.“If you fire me, it's okay. I'll keep creating missions even if I end up in a garbage dump, and I'll come back for your heads someday.”Two system messages flashed before him.[Your actions generate money, and money makes you stronger.][You have the ability to create missions.]Under the influence of his newly acquired Class, he will delve into all the magical paths this world offers, become embroiled in political intrigue, and conquer kingdoms on his own.“Money? I'm the God. Women?” That's fine—I have plenty.

Our protagonist Caam is a man from Earth that was reincarnated into this world as a demon. In order to survive, he spared no effort in avoiding the sparks of battle and without noticing it, he became strong himself.