Creatine will in no way interfere with you losing body fat, if that is your goal. Creatine will help you keep your strength up and your muscle cells volumized, which is imperative for triggering muscle growth.
Some creatine's will have you hold some subcutaneous water, which will blur some cuts slightly, but this can be remedied in a matter of days if you were looking to "peak" for photos, a vacation, or contest.