Two in the pink and one in the stink is a hand gesture also referred to as the "the shocker." It is meant to represent a sexual act in which two fingers stimulate the vagina and clitoris (pink), while the pinky is inserted into the anus (stink).
Wikipedia Commons, Cardsplayer4life
While the sexual act two in the pink and one in the stink represents is definitely a legitimate form of manual stimulation (although perhaps not the most effective one), the hand gesture has appeared all over pop culture. In 2016, Disney's Hollywood Studios' Rock'n Roller Coaster digitally edited a 20-year-old video of Aerosmith lead sing Steven Tyler making the gesture. Internet memes of what is believed to represent two in the pink and one in the stink from the children's show Spongebob Squarepants have also proliferated online. In fact, this gesture is common enough that many people are surprised to learn of its sexual connotation.
