So is Wilfred representative of that part of Ryan's brain he doesn't really want to listen to. Ryan is concerned about being a nice guy, and yet he succumbs to Wilfred's generally bad suggestions all the time on 'Wilfred' (Thu., 10PM ET on FX).
This week it was about Jenna and her boyfriend Drew. The main reason Wilfred seems to hate Drew is that Drew has complete control over him, like the alpha male of the pack. So he concocts a plan to have Ryan pull the super-competitive side of Drew out.
This is a side that Jenna hates, and it works. She breaks up with him. Mission accomplished. Well, according to Wilfred it is, but Ryan's pesky conscience keeps getting in the way, and he wants to set things right. So Wilfred poisons him.