Just the idea of being in a one room with bloodthirsty monster, does not make you feel nice. Even when there are lots of them. Redeem dying, or dead girls and set them free. How? You must defend them against zombies, until they awaken. Stand next to the girl to see a clock and when monster shows up, kill it by pressing left mouse button.
When time is up, the girl awakens and is redeemed. Later it gets harder and zombies are more aggressive. The game has nice sound and suspense and there are new weapons.