It's a French sexual term for when your partner holds your penis in their mouth beyond the point of erection to the state of limp, mushyness like a piece of soggy, wet bread. Then, you smack your partner in the head with your flaccid unit and moisturize their face with your ejaculatory fluid. "Pain" is the French word for bread.

When you eat dirt for the first time and leave your family to build a shack in the woods