What does homosexuality mean? Or bisexuality? Or, for that matter, any other form that may exist.
I find it insulting to the concept of person-hood that one is defined on the basis of attraction to someone else. I’d like to propose as basis of sexuality one’s own individual erogenous zones. For example, some people who may get aroused upon anal stimulation should just be classified thus. To assume this biology is strictly coupled with another person or worse that person’s gender is unacceptable, in my experience; nor is the presumption of erogenous zone rationing.