What does tossing my bf's salad mean?

He ask me to do it and I was lost!What does tossing my bf's salad mean?
Tossing Salad: Contact between one person’s mouth and another person’s anus.
Tossing Salad - Another prison act where one person is forced to basically chow asshole with the help of whatever condiments are available, i.e. Jell-O, olive oil, etc.
That means he wants you to lick his booty. Have you not heard of that before? A lot of prison inmates use that expression.
think he wants you to lick his anus...not sure why the word salad is used
he want you to lick and stick you tounge in his butt!