Who's Topanga?

The following is a post from James: This won't make sense to most of you... We are curious as to who "Topanga" is. "Topanga" is my mystery poster who seems to enjoy reading about my family and I guess was in Puerto Rico with us? Topanga is a character on an older ABC TV show - "Boy Meets World". I hate to admit that I new that and did not have to Google it. So, "Topanga", if you don't mind... who are you?? And why do you call yourself "Topanga"?