A literally connection between two entities isn’t the most original take on the theme, but the execution is what’s important. I love the sub-atomic theme, the artstyle and the general tension created by the music. It does take a bit to get used to but once you do, it’s kinetic and very satisfying. Also props for using PICO-8, that’s always legit.
As other have said, collectibles would greatly help encourage players to move. Other than that, I’d say that once your “partner” is gone, you can do nothing but stand there and die. That’s maybe a bit too sudden. If the particles could take a bit of a beating I feel like the overall experience could be smoother and less unfair at times.