Gameplay Waifu vs Evil combines elements of horror and action, as well as sexual content for gamers to hunt for. The perspective is presented from a first-person view, and the event takes place in a small town at night. An alien ship with armed and hostile creatures landed on a residential area. They killed most of the inhabitants and hid the collectibles.

The walkthrough focuses on obtaining 10 items, some cards with images of nudity and half-naked anime girls. The more photos the player collects, the more intimate the subsequent ones become. Each image is guarded by a certain number of monsters and a mini-boss. The main character uses firearms, like a pistol, shotgun and more. Each type of weapon has its own parameters and damage.

Melee weapons are available that do not require ammunition and deal good damage to opponents, but their effectiveness decreases due to the need to get close to opponents. The ward has a flashlight from the start of the passage, which helps illuminate the locations, since they are always dark. The game world is open for exploration, and the user can collect 10 drawings of girls in a non-linear manner. Dangerous zombies have their own skills and characteristics, differing in their danger and power.