I’m far from fluent, but with the third(?) patient, notice how they say “oku” and “oku made”. That means “deep” and “all the way deep”. Also, note the word “motto” (“more”) as the patient requests she go even deeper. In the last two, as the patients are poised to penetrate, listen for the words “nama”. That means literally “raw” and figuratively “condomless”. Throughout she uses “gomen” to apologize when she needs to correct technique. “Kimochīi” means “pleasurable”.