In the story of Frankenstein, there are three real monsters: society, Frankenstein, and the creature. All three of these monsters have qualities that are threatening and lead to harm. In the story, the most obvious representation of a monster is the creature that Frankenstein created. The being had a hideous and disturbing physical appearance that was able to frighten and disgust any human being. To go along with his monstrous looks, the monster became a killing machine. He killed William, Frankenstein's younger brother, Elizabeth, his wife, and also Henry, his best friend. This beast possessed all the necessary characteristics of a true monster: unnatural and extreme deformities, wickedness, lack of humanity for other humans, and the ability to kill.
While the creature may have had all the traits of a monster, Frankenstein, his creator, is a different definition of a monster. Frankenstein was a monster being that he toyed with nature and tried to play the role of God; he used his genius to unmorally create a human being. The scientist ultimately became a monster because of the results of his experiments. He put not only himself, but his family and the world as a whole in danger because he longed to find and recreate the spark of life. Frankenstein's lack of cognition and his selfish desire to achieve outrageous scientific goals made him a dangerous and harmful being as well.
The last monstrous presence in Frankenstein is society. In the story, the people of the towns in which the creature visited were extremely cruel; they only took the time to see the monster's physical appearance without taking the time to see into his kind, gentle heart. As stated by the monster in Chapter 10, "All men hate the wretched; how then, must I be hated, who am miserable beyond all living things! Yet you, my creator, detest and spurn me, thy creature, to whom thou art bound by ties only dissoluble by the annihilation of one of us.