Well, it’s kind of a trick question, as no one IS bisexual. It is just a label to identify people who have sexual inclinations for both people of the same sex as well as people of the opposite one. The one for the opposite sex is natural, while the one for the same sex is unnatural. The same-sex one is a disorder called Same-Sex Attraction Disorder (SSAD). Here’s a link I suggest you read regarding it: https://cultureoflife.org/2005/11/21/the-origins-and-therapy-of-ssad-same-sex-attraction-disorder/. God bless! (: