She's taking a long bath, exuding pheromones while soaking in the tub, wearing seductive loungewear in a private moment with her older sister, teasingly revealing her cleavage and tempting me. The strange atmosphere makes me tense and excited, causing an instant erection. Whispering in my ear, "I'll do something naughty for you," she delivers a romantic tongue kiss, then grabs my crotch and brings me to immediate climax with handjob and blowjob. Even after she falls asleep, I'm called into her older sister's room, where another blowjob pushes me to erupt once more. Technically it's not cheating as long as we don't have sex—but when summoned in her absence, I end up crossing the line with her sister.