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After the gang got a little pyromaniacal at the Mandibles' place, nothing's as it should be. Wally has suddenly turned into an eternal optimist, Vampire Dad wants to give the twins up for adoption, and Cheyenne has been acting awfully, well, hypnotized lately. Meanwhile, everyone in downtown Cincinnati is snotting and snuffling from a mysterious and deadly flu virus--and the ont larvae are quietly gaining strength underground.
    

Luckily, a suspicious stranger with a syringe shows up to give Wally a free "vaccination." (Now, there couldn't possibly be anything wrong with that picture, could there?)

Nobody wants to adopt the Shluffmuffin twins. Wally's feet stink something awful, and Cheyenne is allergic to everything. Then why are the Mandible sisters so eager to take them home? And what sort of old maids would choose to live in a place called Dripping Fang Forest, where zombies wander the woods singing "Itsy Bitsy Spider" and ten-foot-long glowing slugs want to suck the feet right off your ankles?

Would it seem ungrateful of Wally to point out the Mandible sisters' extra arms? Or to question their all-chocolate, all-the-time menu? Or, um, to venture into the cellar, where the twins have been told to NEVER, EVER, EVER go?

Yeah, perhaps that last bit was a mistake. Now there's nothing left for the Shluffmuffins to do but run--run for their lives!