Regarding Roman attitudes towards large cocks, a bit from the Satyricon by Petronius, C. 65, principate of Nero.
(in a public bath, Eumolpius talking about Ascyltus, after trying to read his poetry aloud and having been shouted down)
On the other side of the room stood a young man, stark naked-it seems he'd just lost all his clothes-and bellowing away loudly for someone called Giton. But you know what happened? The little boys started to jeer at me and imitated me as if I were completely mad, while a huge crowd gathered around the other fellow, all of them clapping their hands and gaping with admiration. As well they might, for that man had a penis of such extroadinary length that you would have thought that the man was appended to the penis rather than the penis to the man. What a Hercules! Why, I'll bet that man could start today and still be going tomorrow. I don't need to tell you that he soon found someone to give him a hand. A Roman knight-notorious, I was told for his strange tastes-threw his cloak around him as he prowled about and then led him off, doubtless anxious to savor his find in privacy. As for me, I doubt I could have even recovered my own clothes from the attendant if I hadn't found someone to vouch for me. But it shows how much more it means in this world to have a great tool than a grand talent.