Can you recommend any novels about the underworld? Thank you!

The first requirement was that the protagonist had to be strong, and it would be best if he hid in the school. Second requirement: Family background. It would be best if he had no family or was a senior leader of the central government. For example, his grandfather was a senior leader of the central government, or he had a hidden background. The third requirement was the protagonist's personality. For example, he might be a playboy in front of the world, but behind him was a powerful underworld boss, or a hidden boss of the underworld. Or, he might be a poor student on the surface, but behind his back, he was a person who sought to kill or rob or find women (the kind of women that the protagonist was more romantic) for pleasure. The fourth requirement was that the protagonist should be rational, cool-headed, passionate, or cold, and talented. The fifth requirement was that the plot should be rich, with at least a few women or girlfriends. Furthermore, the female lead could be a strong woman or a woman who was married. However, it would be best if she was a childhood sweetheart. Otherwise, the two of them would be very loving and trust each other. [Sixth requirement: Clear purpose and clear expression.] "Little White" was also fine. The last basic requirement was that he had to finish the game! "Superpowers, possession, and rebirth are also okay. To be honest, bad guys are not bad. However, it was still a little lacking, so I didn't watch it. Moreover, I hoped that the main character would be more 'flirtatious' in appearance. But his heart was still "romantic"! What nonsense. The main thing is that the protagonist's character is the best to be cold to his enemies. The "cruel" is to treat his women, friends, family, and brothers very well. Do you understand this? Furthermore, the negative situations were all very hidden!