That is extremely big so it could pose a problem, but i suppose you will never know until you try! Maybe some of the ladies on these boards can give you some advice. Good luck!
THAT is big nut not EXTREMELY big and millions of people all over the world dream of having a bf this size. If it does not work for you pass him on -- many others want him! You should consuder yourself fortunate and learn how lucky you are!
worry about what...you think he's too big?? With a little persistence and patience...and a lot of lube...it will fit. AND if you break up and your worried about whether your pussy will tighten back up for the next guy...yes, it will tighten back up. Ever hear of Kegels?? Look into it. Then you'll never worry again. It makes it your pussy [or ass] snap right back into place, just like a Venus Fly Trap. So the next guy will never know the difference, and the current guy will think you've got the best pussy in the whole world.
P.S. If you didn't already know. The average penis size is 15.5 cm long and 12.7 cm thick (circumference). [6" x 5"].
I do say its probably to big for me, but if your willing to put in the time , effort and sacrafice a little initial pain it will pay off and should be amazing in the long run