We recommend using the term "bi" rather than "bisexual". Bi is an umbrella term used to describe an emotional, romantic and/or sexual orientation towards more than one gender.
Don't use bisexual because that orientation is now, like all the rest, based on gender.
'Bi' can now be comprehensively heterosexual, or homosexual, according to stonewall.
Gay can be bisexual or heterosexual and of course so can lesbian, which can also be gay. Or straight.
It really is jibber jabber.
There is no sense to it.