As an American English native speaker, this cartoon made no sense to me, either. I asked my son, a Cthulu fan, if I were missing something. He says the cartoon is from this website:FAQ, in the archives as #277, and that the web designer is French.

My best guess is that translationsnmru is correct, that Wolf had provided the human toast hors d’oeuvres. I think the sentence should read:
"But the human toasts we asked OF Wolf, yum, yum." or (slangier), "But the human toasts we asked Wolf FOR, yum, yum."

At least, in English, we barely have to worry about cases after prepositions, but they still can be confusing...