Perspective from game tester and user-experience designer.
The most important button seems to be the + button to create more souls, but it's covered by the Full-Screen button so I surprised myself first time I went to click it. Animations surprisingly good, it's fun and satisfying to pop the heads, I don't know what else I should be doing if I have to kill to progress it's like why would I want to save them with food and water or let them die naturally. I got the neutral ending, due to reveling twice and repenting once. Only tried the one time, Would be interested in trying again, especially a future build if you keep iterating on this game.