It is a woman, he perceives her as a woman, and he has lust. If the monk, referring to the anus or the vagina of the woman, praises, disparages, requests, implores, asks, enquires, describes, instructs, or abuses, he commits an offense entailing suspension. … (To be expanded as in <a href='https://suttacentral.net/pli-tv-bu-vb-ss2#3.1.3'>Bu Ss 2:3.1.3</a>–3.1.49, with appropriate substitutions.) …

Referring to the private parts of two beings of the same kind