Tenorio Trementina is a truly sinister character that stands for evil in the novel, as his own name indicates (the name evokes the character of Don Juan Tenorio, a corrupted and devilish seducer in the play of the same title written by Spanish playwright José Zorilla in 1844). Tenorio's daughters perform a black mass in order to place a curse on Juan Luna, one of Antonio's uncles. This is the catalyst for the mortal confrontation between Tenorio and Ultima, who plays the role of the good witch in the novel, and by extension between the Marez and the Trementinas. Narciso's murder in the hands of Tenorio in the midst of a blizzard, which Antonio witnesses, is a turning point in the novel, for it reveals to the young boy the nature of evil. The ensuing high fever populates his mind with torturing nightmares that reenact Anonio's spiritual angst.
Both Gabriel and Maria Marez hold Ultima in high respect and do not hesitate to defend the old curandera against the accusations of witchcraft made by many in the village. When a mob led by Narciso comes to Gabriel's house claiming Ultima, Gabriel does not hesitate to confront the crowd with his gun, enraging even further Tenorio, who now sees the Marez as his enemy. In the deadly feud that follows, Tenorio and Ultima engage in a battle which can be read in religious terms as the dispute between Good and Evil for the human soul, represented by young Antonio, who is almost killed by Tenorio. The harmony of nature has been altered by the dark presence of evil and it will be restored only with the passing of Tenorio and Ultima.
As for the rest of the Marez household, Antonio's siblings do not seem to be directly affected by Tenorio's hatred. The older brothers, marked by their participation in WWII, seem displaced in the small town, unable to re-adapt to the simplicity of life in Guadalupe, and eventually move elsewhere, haunted by the memories of the atrocities of war. His sisters, on the other hand, seem to be satisfied with their dolls and their English language.