@Nez It's not like I'm qualified to speak on the matter, but there are many people who are bisexual, and there are many people that have straight relationships their whole lives and one day they fall for a person of the same gender. There are people who fap to gay stuff (like this) even though they're straight. I know I do. I'd also kill to be a girl who loves girls, but who wouldn't How exactly would you categorize those people?
I might have failed a bit in saying 100%, in the sense that how gay or how straight you are isn't actually measurable, like saying 'I'm 55% straight!',but rather,you might have a few tendencies that define homosexual people even though you think of yourself as straight.
If that makes any sense.