In modern times, gay men and women are essentially viewed as their own social classes, who homogeneously only want to have sexual relations with other members of their group. Certain physical mannerisms or even genetic characteristics are often assumed to signify that a person is homosexual. Homosexuality, much like heterosexuality, is viewed as rigid. A gay person was a gay person since birth, and will be until they die. It is impossible for sexual orientation to change.

Before the 19th century, before the concept of homosexuality emerged, were there any known descriptions of people who would fit the modern definition of a lesbian or a gay man, in that they were sexually attracted to people of their own gender and never assumed to be interested in people of the opposite gender? Is it presentism to assume that kings Edward II and William Rufus would identify as gay, were they alive today, as sexuality at the time was defined by acts rather than identity?

Are there any known examples of a person being described as monosexual and gay? By this I mean, any reference to "John has sex with men and not with women", as opposed to "John had sex with a man once".