Schrödinger's Sexuality: Demi-Bisexual, it means that the person in question is half Bisexual which in turn denotes that they are either a Homosexual or Heterosexual but nobody knows if they just say that they're Demi-Bisexual.
I'm Demi-Bisexual. (Meaning that he is either Heterosexual or Homosexual, but you don't know. That's what makes it Schrödinger's Sexuality)