I must say I had a good time with this VN! Cal and Mikkel's relationship was a good basis to what followed, it gave a sense of comfort and sweetness before hitting us with the depression.
The twist is great, although it leaves me wanting more, both on the potential horror that it could bring and on the investigation part that really caught my attention. I believe you said this VN was a prototype for something longer, so maybe, I hope, we'll see more of it! If I had to find a negative criticism to give to the story, I'd say Mycroft could use a better introduction, maybe something smoother. I know you want to play on the randomness of the event, but I believe there might be other ways to do it while maintaining that theme. The presentation is great, be it the CGs, custom backgrounds, custom sprites, and even the small changes to the base sprites of the jam. The music is used efficiently, I can say the technical part was totally mastered! All in all, a great addition to the May Wolf jam!