This is a solid little platformer that does a good job of making its gameplay and story feel related! Having the mysterious elements occur while you're running from place to place doing your errands was a smart move to make said mystery that much more mysterious. I also like how those journeys between events give you time to think about what's going on. It's simple, and there's admittedly still a teeny bit of a disconnect, but it's effective and still works overall! It also helped me feel like I was getting better at playing it as I continued to ponder the mystery at hand. :P
I enjoy the pixel art in this one, as well. You make some pretty good color choices here, and those particle effects paid off, even if they could be a little distracting at times.
I have but one small nitpick: at the initial murder scene, I feel like the effect would have been helped if the blood was actually visible. At the perspective and scale, this might have been a little difficult to pull off, but having some of the ground around the body being colored red - or maybe even some red on the body - would have done wonders for the moment.
As it stands though, you did a bang up job!