What might the meaning be behind these fellatio ceramics (or “penis pots” as I’ve heard them called)?

The un-looted examples generally come from elite graves so they may have been status symbols.

Or they may represent the act of passing one’s “reproductive juice” or “ejaculatory fluid of authority” to another, as when a ruler-deity sends a representative on his behalf to deliver a message or as a delegate.

Museo Larco in Peri via WTF Art History. Also check out Steve Bourget’s book Sex, Death, and Sacrifice in Moche Religion and Visual Culture.