Try, " I've got something to say , but I don't want to ruin our relation ship...........Its a pity that you arn't gay...'cause you have one hell of a nice looking cock, I could really give that monster some pleasure........ah well, I'll just have to settle for the fact that, I'm proud to have such a well endowed (well Hung) freind". But don't push it past that, you might be surprised by the results....... and that may be weeks/months later.
Always state your desire, flattery gets you every where, back off fast and leave the ball in his court, be casual and laugh about it, and don't be pushy.
I've never met a truelly staight man yet. All the 100% men on this site wouldn't actually be on this site if they were truelly straight, there must a be a least a little gay curiosity/voyeuristic nature in them, or they wouldn't be on this site.. There are too few women subscribers, here to hold that amount of interest. Even the purist of exhibistionists here are saying something to the gays on here, does that ring a bell?