When you first hook up with a girl and you slip your two fingers her vagina to get a good (specimen). Once a good specimen has been cultured get in close and give her a hug and smell your two fingers in this process. 1 being no smell and taste like water while 10 being the fishiest cod oil stank cooch on the planet. Never proceed with a girl who rates 5 or above the Ph Scale
Dude you slammed kate last night, how did she rate on the PH test?