I've discussed erotic Moche pottery before here and here. Those should give you a general idea of their "meaning" as archaeologists see it. To paraphrase, the art draws from a diverse yet specific set of scenes. In many of those scenes, the dominant meaning is not the sexual one- a ruler seated on a throne or a partially wrapped mummy receiving oral sex suggest something beyond the sex act itself. If this is what you're hiding from your pops in a box under your bed, well, I know a place for people like you. Likewise, there are things conspicuously missing, most notably any kind of vaginal intercourse is super rare. Lastly, these vessels come almost exclusively from burials. This makes it very hard to determine how they were used. We do know, however, that these pieces rarely have much wear on them, so any use was minimal, be that in pre-burial rites or by, uh, hotblooded young Mochicas with coca leaves burning a hole in their pocket.