I have some ideas
1. Add the passage of time, add stamina, add satiety, add ghost soul strength settings, and use sex to increase their strength (this option allows ghosts to exist for a long time when they appear in the town at full level)
2. You can add a background setting where the entire city is arranged in a huge summoning array, and the house opposite is a summoning point for easy addition of ghosts or DLC in the future
Players can learn summoning techniques in the school library and use special items based on the characteristics of ghosts to summon them at midnight. They can also make ghosts appear automatically in special scenes (ghosts that appear on their own will distort reality). Players need to be prepared to capture and negotiate in the inner world
The newly summoned ghost part is set to have no physical existence and cannot have sex. The protagonist needs to find or buy some items that correspond to their characteristics so that they can stay and rest inside, such as a half body silicone doll with a beautiful image. One by one, they can make mirrors, armor, umbrellas, video tapes, and artificial people in the laboratory
The bodies of the 5 ghosts require players to find materials and hand them over to the ghosts to create their own bodies. During the manufacturing process, the ghosts will have a dialogue with players to choose whether to start from the buttocks or the head. After creating a part, they need to have sex to allow the ghosts to absorb the essence from the body and replenish it to increase their soul strength. Only then can the ghosts create and control more bodies
I have several ghost images that I feel are good about
The ghost with an umbrella or jellyfish on its head floats two stories high in the town
Zombies without limbs controlled by talismans
A weak soul body living in an airplane cup sized jar with its butt facing outward
Cthulhu creatures squeezed in armor
A house can also be a huge ghost, they can transform human bodies from walls and floors