Has Sanada Solved the Case Today? [Crossover]

Harukawa Karin really never expected to run into Sanada, whom she hadn't seen in almost four years, in a situation like this. "What was your relationship with the deceased?" Sanada asked. "Sorry, I don't know him at all." Karin tilted her head and thought it over carefully, sure that she'd never seen this customer before. "Then could you describe what happened at the scene?" In such a perilous setting, the most beautiful flower of all, love, bloomed. Friends, I'm planning to start charging for this on September 20, 2018, starting with chapter 18. There are only 40 chapters, after all~ The investigation parts might make the story develop a little slowly!!! P.S. This is a fanfic I promised my roommate I'd write. I think romance alone is boring (I'm not great at writing romance), so I made it a crossover. Please note: 1. The lousy author goes by A Fei. I'm trying hard to write better, but my basic skills aren't great. I'm doing my best to get the characters' intelligence up to par. 2. As long as you don't give me a negative rating, I'll take anything you say as proof that you love me, as long as you don't use words that go against core socialist values. 3. This short-to-medium-length story is complete. Premise: