The Sponsor Bunny is a bunny that is from a hallucination of Barney.
Moe tells Homer that he finally got Barney back on the sauce, and if he doesn't have fun, he could easily slip right back into sobriety. Barney tells Moe not to worry, because if he feels the urge to sober up, he will just talk to his sponsor, who is the Sponsor Bunny.
Upon being mentioned, the Sponsor Bunny appears next to Barney, and asks him to drink so that he will not die.
Behind the Laughter
- The Sponsor Bunny is probably the reason why Barney gave up rehabilitation and started drinking again.
- The Sponsor Bunny is most likely a parody of the Social Bunny from The Sims 2.