Chichi

Chichi is an informal term for breast. Bubis, boobs, and tetas, tits, are also possible. A large-breasted woman could be described as chichona; or pechugona, from pechos, breasts.

Panocha

Panocha is pussy. Whether this term offends depends upon the company you keep. More obscene is pucha, cunt.

Pilín

Pilín or pilincito, is a childhood term for penis, especially a small one. I equate it with weiner. A more generic term for penis is pito, dick, literally whistle. A large penis would be a pitote. The most common slang for penis is verga, cock, doubling as a general-purpose obscenity. Big-dicked is vergón.

Huevos

Huevos, eggs, are balls (testicles). To refer to them with affection, there's huevitos.

Nalgas

Nalgas refers to the ass cheeks. Me tocó las nalgas. He touched my ass. The singular version is also possible: Tiene buena nalga. She has a good ass. Trasero is rear end, butt/bum. Ass or booty is culo, which also works for anus, asshole.