Sex that is not Brown, Red, Yellow or Black. i.e. masturbation, oral, 69, frottage only, definitely NOT anal. From the fact that both vanilla ice cream & spunk are white. Originating in the gay scene, especially by wearers of coloured handkerchiefs which indicated visually what they were into. Now debased by other MSM as 'normal' or not kinky.
Hey mate, you into fisting? Sorry, only do vanilla these days.