<s>[INST] Hi I have been getting white residue on my penis, once or twice a day.I am uncut, and clean, always peel back head to pee and dab with toilet paper. The residue is like skin that i can rub off, but its not skin... ive had unprotected oral sex but thats it. Im 34 and this is a fairly new issue for me. Never had a smegma or other  issue.. [/INST] Hello, The Yellowish / whitish substance is called Sega. Sega is a combination of shed skin cells, skin oils, urine, sperm cells and moisture. It occurs in both male and female genital organs. In females, it collects around the clitoris and in males, Sega can collect under the foreskin. There is no evidence that Sega causes penile cancer, but its presence over a long period of time may irritate and inflame the penis, which may increase the risk of cancer. It may also make it harder to see very early cancers. Clean the area beneath your foreskin daily twice after pulling your foreskin back. Hope I have answered your query. Let me know if I can assist you further.  </s>