I am 100% straight. I have never experienced an attraction to women while I have experienced attractions to men. I was this way in early childhood too before hormonal changes. I always wanted to be with a guy and I'm actually quite turned off by women.

However, I still subscribe to the idea that sexuality is on a spectrum and fluid. It's not common, but there are people who identify as straight for years and years and never experience any homosexual tendencies until one day meeting someone of the same sex that they experience an attraction to for whatever reason. Plus there are plenty of people who identify as straight but occasionally have homosexual fantasies or have someone of the same sex they say they would "go gay for". I don't have any fantasies of that nature or any "girl crushes". However, I don't think that just because I have not experienced anything of that nature that it means it's completely impossible. I don't think it's likely that I will, but I think human sexuality is much more complicated than "gay" and "straight".

I could be wrong. There needs to be much more studies done on the topic of sexuality.