Rosario

Griselda practiced Palo as a spiritual tradition that blends African religion with Catholicism. However, her rituals were not meant to harm Rosario, instead, she was using daily blood sacrifices to keep the evil spirit Kobayende at bay and protect her family. The blood offerings were a desperate attempt to contain the demon her husband had unknowingly unleashed through his own pact.

Earlier scenes show Griselda maintaining a hidden chamber with occult artifacts, suggesting she was deeply invested in spiritual practices long before the main events.

Kobayende is an evil spirit that Griselda's husband made a deal with to help realize his dreams. The spirit grants power but demands blood sacrifices in return. Kobayende seeks to possess family members and continue its influence through generations. It ultimately wants Rosario specifically, possibly because she represents the next link in the family bloodline.

The film establishes early on that Griselda performed daily blood rituals, hinting at an ongoing bargain with a supernatural entity.

Rosario's father made the original pact with Kobayende to achieve success and prosperity, he wanted the financial success that Rosario would later attain as a Wall Street stockbroker. When he couldn't maintain the required sacrifices, the burden fell to Griselda, who offered her own blood to protect the family. The revelation that the father, not the grandmother, created this dark legacy is the film's central twist.

The neighbor Joe hints at a family secret when he tells Rosario about her grandmother's protective role, suggesting deeper layers to the family history.

Rosario was in danger because Kobayende wanted to possess her as the next family member in the bloodline chain. Since her father made the original deal, the spirit had a claim on his descendants. Griselda had been sacrificing her own blood for years to keep Kobayende away from Rosario, but when Griselda died, the protective barrier broke, leaving Rosario vulnerable to the spirit's pursuit.

Griselda's death is what forces Rosario to return to the apartment, removing the grandmother who had been actively protecting her.

Rosario saw visions of her mother Elena as a decaying corpse because Kobayende was using her mother's image to psychologically torment her. Since Elena died before the events of the film, her appearance as a rotting corpse represents the spirit's attempt to frighten Rosario and break her resolve. The visions intensify as the spirit's influence grows stronger throughout the night.

The supernatural activity escalates progressively, with the visions of Elena appearing after Rosario discovers the hidden chamber.

The doorman scene serves as a cruel false hope before the final twist. Rosario helps the doorman, showing she has overcome her previous selfishness regarding people of lower income, a character flaw established earlier. This act of kindness creates a moment of normalcy before Kobayende's hand bursts from her mouth, revealing the spirit never left and has been inside her all along.

Earlier in the film, the doorman asks Rosario for help, but she dismisses him due to his low income, establishing this as a character flaw she must overcome.

Griselda was not the one who made the deal with Kobayende, that was her husband's action. However, she discovered what he had done and spent decades sacrificing her own blood to keep the demon contained and protect Rosario. Her death inadvertently released Kobayende from the constraint her blood had maintained, setting the horror events in motion.

Griselda's apartment contains the hidden chamber with occult items, showing she was deeply involved in spiritual practices connected to the spirit.

Joe, the neighbor, helped Rosario because he knew about her grandmother's protective rituals and understood the danger she was in. He provided crucial exposition about the Kobayende deal and tried to assist her during the confrontation with her possessed father. Unfortunately, Kobayende killed Joe during the attack, using the father's body to murder him when Joe tried to intervene.

Joe approaches Rosario earlier to share information about her grandmother's practices, establishing his role as an ally.

The hand bursting from Rosario's mouth confirms that trapping Kobayende in her grandmother's corpse did not work, the spirit had already latched onto Rosario herself. By killing her father, Rosario thought she was free, but the demon was simply waiting inside her, using her as its new host. The bleak ending suggests the curse continues and Rosario will become the next vessel for Kobayende's evil.

When Rosario performs the ritual to trap Kobayende in her grandmother's corpse, the spirit's response suggests it has already chosen Rosario as its true target.