To each their own, but personally I find women with tattoo's sexy. I don't mind a tattoo located on her breast either, especially if its a flower like you described. Then again, I'm also a Fan of the more Morbid tattoo crowds, so if she had peeling skin, bones, skulls, devils, demons, rips, thorns, barbed wire, etc... on her breast I would like it even more..
Again, just my opinion amongst millions of others