Go for it raddy! Don't come away thinking I wish I done this or wish id done that.
I've sucked cock, fucked the bf of a WG and been fucked by him. Sucking cock is great fun, very naughty and even better if she's encouraging you both.
My ultimate fantasy is to have a guy cum in my mouth whilst she wanks him and I intend to tick this off the list before the year is out. Punting is about making fantasies happen, for me at least and that is my aim going forward. You'll get some stick, called gay and so on, just ignore it. I know I'm not gay - the first thing I do when a half decent bird walks past is check out her arse.
Good luck, be brave and most of all, enjoy yourself. Oh, and report back once your mission is complete!