"A demon," Lars answered grimly, peeling himself off of the wall. "One that's overtaken a host. They're rare, but they've been getting increasingly more common with every day." 

Lucas was already slinking out of the room. He was definitely not very sociable. 

"Demons that possess people, like they did to Mrs. Reynolds's son, can't overtake the human form on their own. They need help. And that's the most disturbing part: someone is creating these things. Taking people off of the street, and forcing demons inside of them." Lars seemed very heated about this topic. This was clearly a very personal fight to him.