In a fantastical land, there are two types of creatures: Cherubs, whose statements are always true, and Demons, whose statements are always false. Four creatures, Alex, Ben, Cara, and Dan live together, and they make the following statements.

Alex: "Ben and I are different species."

Ben: "Of the four of us, there are exactly three Demons."

Cara: "Dan is a Demon."

Dan: "Cara is a Demon."

How many of these creatures are Demons?