Ward of dementors with a patronus charm which defends yourself against dementors who guard the Wizarding World prison of Azkaban. Dementors joined forces with the Dark Lord, during the second Wizarding War of 1997-1998 when it was ended at: The Battle Of Hogwarts, 1998, August 31st- September first
Dementors, who appear invisible to Muggles, can detect a person by using their mouths underneath their hoods, from where they suck information of memories out. Lastly, dementors may perform a sucking, known as: The Dementor's Kiss, which if pursued, sucks the soul; out of the mortal's body and they appear souless, without conscience, brain, understanding, or ability to move in any way. They are living but just a State-Of-Mater.
The Dementors Kiss ,has not been inforned of knowing to be used upon a Muggle, neither has it been recorded for being used on Magical Creatures. The only flaw in the dementors path of coldness and despair is the strong bind of real, pure happiness, ~Nox~.