In my personal life the term that bothers me least is "front hole", as other things tend to give me gender dysphoria, but the least-bad and the one which I'm happiest using is "cunt" - others feel too feminine for me! For clients, though, I refer to my "pussy" (a term I would never, NEVER use in my personal life!). I really hate the term 'vagina'! I'll also let clients refer to my "clit" though it's really my penis or cock...