I was going to write this in the comments of @stamos's stellar list about her bad Tinder date (go read it, I'll wait) but then realized it was fodder for a list of its own. You're welcome.
  1. So @stamos and @samboyd have confirmed that this instruction means to suck each dick in the bag individually. This raises a LOT of questions.
  2. First, where does one get a bag of dicks?
    Does the person who is instructing you to do the sucking bring you this bag? Is there a Bag of Dicks emporium somewhere?
  3. So these are individual dicks in a bag...are they attached to people?
    Are there people in this bag? Can they breathe? How did they end up the unlucky folks to get shoved into a bag for dick-sucking purposes? Or maybe that's something they're into?
  4. If they aren't attached to people, HOW THE FUCK DOES THAT WORK?
    Seriously. Is it just a bunch of organs flopping around in this bag? How did they get detached from their owners? Is there a black market for disembodied penises (maybe run by a dude who hangs out at the Dick Bag emporium)?
  5. I guess what I'm saying is if/when someone says this next I am going to ask them all of these questions, but in the meantime maybe some of you nice folks can help?
  6. Washington residents will tell you that Dick's (Seattle's version of In-N-Out) is a great place to "grab a bag of Dick's."
    Example: "You wanna grabba bagga Dick's?"
    Suggested by @leslie