I used Tretinoin when I was younger on my face because I had a lot of acne. It made my face easily sunburn. I wouldn’t put that on my dick regardless. If I want a moisturizer, I’d stay with coconut oil or olive oil. The penis skin is smoother in general. But I agree with the guys. Veiny and proportionate head to shaft and just be clean and try to smell fresh, if you ever want to get head.