Hi I wanted to know on behalf of my boyfriend who has a blister or a cut he says on the tip of his penis right beside the opening of what it could be. It has discharge a little of yellow watery substance that may be pus and he said it doesn t hurt not bother him. But he wants to know how to get rid of it. It has dried up and a scab appeared but it came off and it s not healing . He has had it for about a week, please help to give your advice or opinion of what it may be and how to cure it. He is clean no and STD s.