The Living spaces in ancient Rome were very open. Homes were generally built around an open courtyard or garden and there was very little, if any, privacy. In fact, they didn't even have the same concept of privacy that we have today. Since Roman society was very public, sex was also much more public. We lean more toward cordoning off representations of sexuality in art, literature, or really anywhere, from the rest of life but in ancient Rome, sexuality was just a part of life. In both Pompeii and Herculaneum, you will see frescoes everywhere of people having sex. Even people who were not so well off, still managed to adorn their walls with this sexual imagery, even if they had to settle for a less skilled artist. The Roman's taste in art was a bit different than ours is today and any proper art collection would have at least some of this explicit art. This artwork was normal, appropriate and expected. These pieces were not trivial, they weren't afterthoughts, they were well done, valued and shown off.