If there is a "Devil" per se.
In scripture, Satan, the talking serpent, is a metaphor for a particular type of person also known as a devil.. In Hebrew the word for serpent, nachash, is both a noun and an adjective which means snake, but it can also mean brazen, shining one, and or one who practices divination, in other words, a religious deceiver.
There is no 'if' about it. Take a good look around. For as long as I can remember there has been a plague of talking serpents of biblical proportions crawling all over the world and countless millions of people have died from their poison once bitten.
Here's a chance to enter that stage of development/evolution to communicate with spirits.
Do you see what I see?
"I see dead people. Walking around like regular people. They don't see each other. They only see what they want to see. They don't know they're dead. There everywhere."
The Sixth Sense (1999)