Truly straight guys don't start threads asking if you can still call yourself straight if another man blows you.
If this question stresses you, if you find yourself giving an emphatic "Hell, no" answer, then you may be suffering from homosexual panic.
Who knows what it means if you like a man blowing you? It could mean lots of things. Maybe it's because you're attracted to men? Or you really like having your cock sucked and a man's mouth is easier to find than a woman's. Or you enjoy showing your dominance by making another man blow you.
Here's my test for what someone's sexual orientation is. If a woman can break your heart, you're straight. If a man can, you're gay. What you do with your cock doesn't change your primary sexual orientation.
And while I think there are men who are as happy fucking boys as girls, I'm not sure I've ever met a bisexual man who have have his heart as easily broken by a man as by a woman.
Maybe they exist, maybe they don't.
But I'm the first to admit that genuine bisexuals (as opposed to straights/gays who from time to time play for the other team) are confusing.