Two men go into the doctor's office and sit beside each other.. After a while they are talking up a storm, and one guy says, "I'm in here 'cause I have a red ring around my dick and I don't know what it is!"
"Well, I'm in here because I have a green ring around my dick! What a coincidence," the second exclaimed.
So the 1st guy goes into the office, and 15 minutes later he comes out and says to the second man, "It's fine! Nothing to worry about!"
Relieved, the second guy goes in, and comes back out crying.
"What happened in there?" the first guy asks.
"Well, there's a big difference between Lipstick and Gangreen!"