The Pet - by Charles L. Grant
Teenagers are being slaughtered by the Howler, a serial killer who stops in small towns just long enough to kill, just long enough to tear apart a family and a community. When he strikes in Ashford, the town reacts-setting limits on teens' activities, monitoring who goes where-and parents become paranoid.
Seventeen-year-old Don Boyd doesn't need the grief. He's already under siege-he's got family trouble, girl trouble, trouble with his high school classes and trouble with the jocks who rule the school. Surely the Howler will kill someone else, somewhere else, and then Don can go back to trying to escape notice.
But the Howler likes Ashford. And one frosty autumn night, the Howler chooses Don as his next victim. The attack is swift-but it doesn't go as planned. Suddenly the killer and the boy are surrounded by an unnatural mist, by green fire, by the sound of iron striking iron.
And then the real horror begins.