😋I recommend you the Underworld Investigation Bureau. The main character, Xiao Kun, was the director of the Underworld Investigation Bureau. Due to a strange combination of factors, he became a human. Then, he was eager to know who he was. This novel is a mystery detective-Wonderful World. The main character is not a saint, but has a decisive and kind personality. There is no female lead, which meets your needs. I hope you like my recommendation, Mwah ~😗