Solving the case is a little bitter, but my sister is super sweet

Lin Xuan was reborn.
No system, no cheats, no golden fingers.
But God gave him a perverted body.
The gears of fate also began to turn at this moment.
…
Mu Qingtian: Brother-in-law, do you have a dream?
Lin Xuan: Yes, I want to show off.
Mu Qingtian: …
Lin Xuan: Showing off is a desire for dignity, a fantasy of reality, and a right to yearn for. What is the difference between not showing off and being a salted fish… Oh, my wife, why are you hitting me?
Mu Qingyan: Vulgar.
Lin Xuan: Yes, as a scholar, this is called showing off in front of others.
Mu Qingyan: …
From then on, Lin Xuan went further and further on the criminal investigation road of reasoning and solving cases!