Hello I really appreciate your concern and being your physician, I will try to help you out in best possible way Looking at your description this could be suggestive of injury or inflammation , STI or other infection and an allergic reaction sometimes passage of concentrated urine can lead to penis spasm. I would like further information to help you better relevant medical history like diabetes or liver disease? is he having any kind of discharge or itching sensation? In my opinion he should keep it clean and apply antiseptic ointment If it gets worsen or doesn t improve than he should consult your doctor for physical check up and detailed evaluation Maintain good hygiene Ask him to have plenty of fluids orally use condoms during sex until it heals completely Hope this answers your question if you have any more doubts please feel free to write back to me, I will be happy to help you Best wishes