If both parties consented to the pictures being taken AND were both over 18, AND the sex act portrayed is legal, it's fine. If one of you looks younger than 18, be prepared for a visit from police investigating a creation of child pronography case. If the photos depict 'sodomy' or bestiality, expect a police visit to determine whether the act photographed occurred in a state criminalizing that type of sex. Don't get them developed in one of those mall places that show the photos to the entire world as they roll off the developer.
This is not legal advice and you are not my client. Double check everything with your own attorney and your state's laws.