Good concept, I would wish the prisoner's falling speed would be a little slower as I have so little time to identify what's coming up from the bottom of the screen, or have more distinguishing colors between what you want to hit and don't want to hit (hearts and several dangerous items all share red, as such my initial reaction to a heart is to avoid it because I just see red).
I like the aesthetic of the game. The ui made me think I was watching these prisoners die through a video feed, perhaps as a warden or maybe a sick patron who paid for that privilege.