I have been with my boyfriend for 3 months and we’ve started to have sex recently. Every time I go down on him I see a small bump on the shaft of his penis that alarms me. It’s soft, rough, skin-colored and really resembles a single wart. He told me that that he’s had this for a long time that I didn’t notice. When we start dating, he said that he’s had sex with a few partners in the past. What could this bump be?