It is used to taunt a guy when he does something stupid or ridiculous but imagines that he has done something remarkable or heroic, and is well pleased with himself about it.

The guy taunted is expected to correct himself or give an explanation for what he has done after this is said to him.

When you want to taunt a girl, you say "Hello heroine!?"

The taunt can be followed by further questioning using "why," "what," when"or how."
You are sitting in your friend's car and your friend overtakes other cars at 90 miles/hour by changing lanes in a ridiculous zigzag manner and you say to him "Hello hero!? What are you doing? We could have gotten into an accident there."
Your friend says "But we didn't, did we?"
by QueenDeej March 26, 2010
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