Best and most memorable sex was fucking my college gf on a boat. We rented a boat in FL for spring break and her family came along. Midway through the day, we docked on a beach that was part of a walkable small island. My gf wasn't wearing shoes, and the terrain became too much for her feet. So her family went on to the other side of the beach while we turned around to go get her shoes before meeting up with them. When we got back on the boat, I grabbed her by the top and exposed her B cup titties. She then pulled down my swim trunks to expose my rock hard cock and dropped to her knees to begin sucking me off. Before I blew my load, I pulled her up, sat down, pulled her bikini bottoms to the side, then had her straddle me. We fucked raw and in the open for 5 mins, with her getting off quickly, then me eventually blowing a load over the boat and into the ocean. To this day, it is still both of our favorite sex memories of all time.