I reckon these are Fordyce angiokeratoma. I don’t know how old you are but they usually appear in older man. They may appear in clusters or you may have just one. The colour may be red, dark red or black. They are made of dilated capillaries and are completely harmless but you need to watch for them when using a towel. You may scratch them (like you did). Then they start bleeding and forming these black lesions that are also harmless.
However, it would be best if you avoided damaging them and prevented bleeding.
It is true that they are unsightly but there is no point in removing them. It is not known what causes them. If they bother you way too much, you may decide to see dermatologist and talk to him/her about having them removed by cryo or another available therapy. They are benign.
Information on this site is provided for informational purposes only.
It is not meant to substitute for medical advice provided by your physician or other medical professional.
If you have or suspect that you have a medical problem, promptly contact your physician or health care provider.