I also agree with the other members.  A good ratio is 1 roo for every 10 hens....Plus, they will have their battles for dominance.  The poor hens will be mated WAAAAY too much and then they'll start looking scraggly, with feathers missing from their backs and necks, and then they will be stressed.
So it would really be a kindness to keep only one, and truly, with just a few hens, none is actually good.  I know people who breed will have a trio or whatever, and then the hens are bound to look crappy.  But you can put hen saddles on them to protect their backs.....
I just like to see my hens looking beautiful and happy......