By this reckoning, one can assume that if a person were to call things "So Straight" all the time, they are merely reinforcing their own heterosexuality. Hence the term "No Hetero"
Steve: I'm pretty good man. *slaps back*
Frank: Hey! No hetero!
Steve: Yeah man. No hetero.
Can be used when a male is speaking to a female, or vise versa, and does not wish to infringe on existing relationships, or if the listener is too ugly to express intimate intentions, etc.
Kelly: Oh gr8, thanks!
Trace: I love you (no hetero)
i like that
its definitely an improvement on the no homo