One possible element could be a creepy old mansion. It might be abandoned and full of dark corners where strange things happen.
Another element might be a strange character. For example, a reclusive hermit who has some dark secrets and whose actions are very unpredictable, adding to the horror aspect.
I'm not really familiar with a specific 'agoura horror story'. It could be about a haunted place in Agoura. Maybe there are tales of strange apparitions in an old building there, like a ghostly figure that appears at midnight, scaring those who dare to pass by.
Ghosts could be a possible element. In 1928, superstition was still quite prevalent, and a horror story might involve the apparition of a vengeful spirit.
One possible element is a haunted location. The princess might live in a spooky castle filled with secret passages and rooms where strange things happen. Another element could be a malevolent force like a demon or a powerful sorcerer who targets the princess. For example, the sorcerer might use dark magic to make the princess see terrifying visions.
Ghosts could be an element. In many horror stories, ghosts play a major role. They can haunt a place, like an old building in Navsari, and cause fear among the people living nearby.
One possible element could be the use of his unique musical sounds as a trigger for the horror. His music often has intense and somewhat otherworldly beats that could be associated with something sinister.
The Detroit Horror Story may contain elements such as the isolation of certain neighborhoods. These areas, cut off from the rest of the city, can feel like a world of their own, full of mystery and danger. The presence of graffiti - covered walls and broken streetlights can add to the spooky atmosphere. There could also be elements related to the city's history of racial tensions, which could manifest in stories of hauntings or vengeful spirits.
The waiter himself could be a key element. He might have a past he doesn't remember, which is somehow related to the horror. For example, he could have been involved in a murder at the restaurant in a past life, and now the spirits are coming back to haunt him. Also, the customers could be strange, like they are not really human but some sort of otherworldly beings just pretending to be normal diners.
Malfunction could be one. Like when it doesn't stop vibrating or changes its pattern unexpectedly.
One possible element is the sudden and terrifying hallucinations. People on bad 'ecstasy' might see grotesque monsters or distorted versions of people around them.
One possible element could be the mystery meat. You know, rumors about what's really in those burgers. Another could be a creepy customer who gives everyone the chills. And then there's the idea of getting lost in the maze - like storage areas or basements in the McDonald's building.