The mechanics are easy. To make it hurt, click on various parts. It will scream or bounce off, and then bleed. This is a realistic effect that scares people even more. If this makes it uncomfortable, you can switch off the feature. Click on the icon with the red drop. Coins are earned by keeping your mouth open and letting loose. They will fall off the creature. When it dies, you get rewarded and the level is complete. They can be used to purchase weapons that will make it more entertaining. They are initially locked in cobwebby. Spend your ingame money to buy them and use these against the beast.
You can also modify the main character. Make it more sinister by adding a mask. There are 8 options to choose from, including a wolf or a skull bat.