I have recently smelt a fishy smell from my boyfriends penis,has he been with another woman and caught some kind of sexuall disease ? I have no smell from myself down below.or could it be some king of infection he has. Please help

Is he circumsized or not? If not then the smell might be from the area under the foreskin. He should keep that area clean and may need to do that several times a day. If it is something you noticed only recently then it will be better for your friend to see a urologist and got it checked.

If he is NOT circumcised (http://en.wikipedia.org/wiki/Uncircumcised), the smell could be due to a lack of proper hygiene under the foreskin. If he is circumcised, it'd would be a good idea to go get STD-tested.
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