Tasting some forbidden fruit?  Thinking about doing something you probably shouldn't?  Regardless of the answers, the Hanky Panky might be for you. The term dates back to the mid 19th century, and the cocktail is from the 1920s. Ada Coleman, a bartender at the American Bar at the Savoy Hotel in London (see London Calling), created it for one of her loyal patrons.

1.5 ounces gin (I used The Botanist)
1.5 ounces sweet vermouth (I love Carpano Antica)
2 dashes Fernet Branca

Combine in a mixing glass with ice, stir with desire, and strain into a chilled glass.  Orange peel garnish optional.

The Hanky Panky has the distinction of being the first gin cocktail in the Den. The sweet vermouth and Fernet Branca act as counterpoints to the gin, so the result is a nicely balanced drink. When using Fernet Branca, remember less is more. Its distinctive taste easily can overwhelm a cocktail.

Modern definitions vary slightly, but the term frequently arises (pun intended) in a sexual context, e.g. the 1966 song "Hanky Panky" by Tommy James and the Shondells.  You may notice a recurring theme with certain cocktails in the Den, e.g.  the Hanky Panky, the Between the Sheets, the Passion, and the Intense Ginger Sutra.  Infer as you like.