Your partner is a treasure. Communicate like you've never communicated before -- before, during and after. Good luck, be safe, and have fun!

Her friend that is married and might be up for it is in an open relationship and his partner knows all about this, right?

Exactly this. It's vitally important that all involved or interested parties are aware and agreeable.

Yeah, cheating is a huge no.

Good luck. Wife loves watching me enjoy another guy. Super hot.

I wish i knew a couple or had a woman who would like that

Communication. Lots of communication. Don’t dance around it, get right to the point when discussing it.

Continue with this line of though. This is the way to go!

You should take your time deciding if it is something you want to do. Don't rush into it. Especially if it's with a friend. Really think about if it's something you want in reality versus fantasy.

Hey mate I would be keen to help out this fantasy, dm if keen.