Step-Mom Is Watching Us...

My stepsister and I have been engaging in some playful banter and fooling around lately. No physical intimacy has taken place, but there's a limit to how much teasing I can handle! How about we escalate this situation? Right now? Our parents are downstairs! Let's just be discreet.
Do you have any protection? No. But I assure you I'll withdraw, I wouldn't want to impregnate my stepsister. That would definitely be uncomfortable.
Alright, let's go for it! We proceed cautiously, careful not to get caught by our folks! I lift up my stepsis's top and caress her erect nipples. Can I indulge in it? My stepsister is enthusiastically embracing the moment as much as I am! After weeks of flirting under the same roof, I finally experience the sensation of her tight 18-year-old pussy lips wrapping around my manhood!! My stepsister and I enjoy ourselves, but just as I'm about to climax, our stepmom unexpectedly walks into the room!! I don't want my stepsister to stop pleasuring me, and our stepmom is completely taken aback when she first walks in! However, the unforeseen occurs. Our stepmom appears to derive pleasure from watching us engage in intercourse. She begins to fondle her ample, natural stepmom bosom, and I even noticed her hand venturing beneath her skirt! I was so distracted by our stepmom that I lost all control and ejaculated deep inside my stepsister's fertile vagina! Oh my, you said you would withdraw!! Apologies stepsis, get dressed, and we'll head to the pharmacy to get the pill for you. Our stepmom hastily exits the room before my stepsister notices she was observing us!.