Thanks for the info on Epaminondas, but I asked for a source and you did not give me one.
Most writings on the subject are by gay apologists. Here’s a reasonably unbiased article.
http://oregonstate.edu/~blakena/cs195/final/Other/Writing/RomanHomosexuality.html
The author stresses, quite accurately, that there were very few homosexuals in the modern sense in the classical world. Bisexuality was considered the norm.
The Emperor Claudius was apparently the only one in the first two centuries of the empire who didn’t do both men and women. He was considered odd.