At first, I thought everyone was attracted to people of multiple genders too and that they’d decide to be either straight or gay (or get categorized à la Harry Potter’s sorting hat maybe).
Then one day, I Googled “I like boys and girls.” When the word came up, I was finally able to verbalize my attractions.
Anyone who's waiting for me to pick a side will be waiting forever because it's never going to happen. It was in my pre-teen years that I began to find boys my age attractive.
It started with a close friend and branched off to other guys I spent time with on various sports teams.
People have consistently asked me these sorts of questions since I was 14, the first time I publicly came out as bisexual.