What was the Clete character all about?

I just watched this for the first time on TV in HD and found it enjoyable, not great but it had its moments. But I don't understand what the Clete character was all about. They sort of made him a little mysterious. Like he was playing around with Peter Weller's character. Kept on egging him on everytime he failed to kill the rat. Also like reminding him about wearing gloves when he never told him in the first place? Were we to awesome he may have been responsible for the Rat(s) somehow? Like he wanted to drive Weller and his family out of the house. He seemed to be in awe of the house when he came in to repair the dishwasher. Similar with Jennifer Dale's character when she first came into the house. Were they aiming at some allegory with Clete living in a basement like area? And what was with the end where he just came into the house by opening a panel and told Weller his bat device wouldn't work?...