For a Roman freeborn citizen it was not important who their sexual partners were. These might have been male or female, including slaves or prostitutes of any gender and age, a wife or freeborn of any gender and age, even though, having sex with the latter would have created legal problems (stuprum). What really mattered to them, however, was that their integrity, as real men (vir), would not be harmed.
For having a stigma of softness or of not being a real man (male marem), to a Roman man meant losing all his privileges and stopped him from taking political office, or joining the army, his credibility would have been lost and he would have become an object of derision.
Roman men were known to be dominant in every aspect of their lives, however, in the beginning they were a sober hard working, practical nation of farmers, and there were no similarities between the early ancient nation of farmers and the later conquerors. Yet, it was exactly these roots of having being born as a nation of hard working, practical people that moulded the character of the great civilisation that was to come.