I'm staying over at my girlfriend's house for the first time. Apparently she lives with her sister, but she's not there today. I take advantage of the opportunity to arrive at her house, and there's a naked gal in front of me... This gal is her sister. And she looks at me with a lewd look in her eyes. The gal sister, who is frustrated after breaking up with her boyfriend, says, "Isn't it okay to just suck it?" and takes advantage of the opportunity to give her a blowjob! It feels so good you'll die!