As a reward for passing the university entrance exam, my sister invited me on a trip to a hot spring just the two of us! My sister loves me and has big tits and is a little naughty. When I saw my sister getting changed into a yukata, my cock got hard, so she gave me a handjob and we had creampie sex in the open-air bath. I enjoyed a lovey-dovey time with my sister, who wanted my cock, just like a lover!