Significance of Mike Ryerson's High School Ring

After Matt chases the vampire Mike Ryerson out the window, Matt has a heart attack. Susan runs upstairs to check on him. She goes into the guest room to get a blanket for him. There, on the floor of the guest room, she sees Mike Ryerson's high school ring glittering on the floor. It is a Cumberland Consolidated High School class ring, engraved with the initials M.C.R., which stand for Michael Corey Ryerson. Hearing the vampire call out, "I will see you sleep like the dead, teacher," and finding the ring make her begin to suspect that there may be real vampires.