Yes they do exist in human society. The souls who have gone to hell after death are spirits that have a strong attachment towards the earth and human way of life. Spirits in hell do not understand they are spiritual beings. All they know is life with a physical body, so they are consumed with the desire to satisfy their materialistic needs.
Because reincarnation from hell is impossible, they aim to possess a person living on earth. By possessing a human being, evil spirits can feel just as if they have their own physical body, feeling the physical sensations and satisfying desires for food, sex, money, power and the like.

The only prerequisite for evil spirits to come and stay with a person living on earth, is to find someone whose mind is on the same wavelength as theirs. Evil spirits cannot stay with a person living on earth if he or she is always calm, benevolent and altruistic. But if his or her mind is dark with hatred and anger stays that way for extended periods of time, then it will attract evil spirits who, being on the same wavelength, can sneak into the person’s mind and stay on earth for five, ten or even many more years. This is what is known as spiritual possession.
You can see spiritual possession videos on youtube. Then decide do they really exist or not.