I had imagined, no doubt to the similarity of the cultures, that they took after the Greeks, not so far as to accept pedastry, but with a leniency or unconcerned attitude towards homosexuality in general. But I've read that it was uncommon and discreetly done for fear of derision, at least. Another of a story of a soldier being awarded the civic crown by the infamous Marius for killing an officer who, as it was put in Life of a Colossus by Adrian Goldsworthy, "had tried to force his attentions on him", assuming that the officer's rank might forcibly persuade the soldier into acquiescing, I imagine. Of course this was all in the late republic era, but was this always the case, even through its later years as an empire? I understand sexuality has a changed meaning two-thousand-some years ago, but a male and male relationship.
This has been written about, extensively, by /u/thebatteryhuman and /u/marsthegodofwar in this thread.
If there's anything you're still curious about after reading that, feel free to ask.