Black spot like thing on dogs penis

Hi, was just wondering if you could possibly tell me what this might be? I noticed it a few days ago and decided to keep an eye on it since it was very small but it’s gotten bigger and it seems to be swollen and it’s red. It doesn’t seem to be causing him any pain or discomfort but I am concerned. Thank you :)

Hello!  I am concerned, too.   There  are several possibilities for lesions in that area, including canine transmissible venereal diseases (a canine STD), skin cancers of various kinds including mast cell tumours or melanoma, but also infections and parasites.  I can't see the lesion very well - it's a blurry photo - but the skin around it looks sore and it's obviously a very delicate place.  We would recommend showing this to your vet, at least for triage, very soon.