I'm pretty sure there's a difference between a fetish and a fantasy. This here sounds like he is fantasizing about a big ol' dong in his mouth. Just sayin
if you've never acted on this fantasy you're not gay.
the first time you do you can consider yourself 'bi curious' and you get a free pass.
if you really like it and pursue it even on a semi regular basis, you can consider yourself bi.
i have learned this over the years from blowing lots of married guys.
most only receive - they dont consider themselves bi; those that return the favor are comfortable with the 'bi' label.