In prison, a choice method for protected sex, especially when obtaining an actual state issued condom seems just too pre-planned, potentially gay or unromantic.
Bro, let’s just go at it and have sandwich baggie sex; it’s not like we’re into each other and planned it, right?
The act whereby a sandwich bag is placed in close vacinity while you masterbate. Once near completion the sandwich bag is placed over the penis to allow for a quick and easy clean up.
Stephen - "Liam, we seem to be getting low on sandwich bags!!"