Penetralia

penetralia \ˌpe-nə-ˈtrā-lē-ə\ noun plural: 1. the innermost parts of a building, especially the sanctuary of a temple, 2. the most private, hidden or secret parts or recesses {the penetralia of the soul}

Etymology: Latin, neuter plural of penetralis inner, from penetrare to penetrate

Those who hear this word will most likely misconstrue its G-rated meaning, so have fun with it.