Sister Strap Sandwich

Casey Calvert and Keira Croft recently discovered that they are both in a relationship with Zoe Sparx. While Zoe played them both, the step-sisters come up with a plan for payback. Instead of separating from Zoe, Casey and Keira decide to confront her together.
To surprise Zoe, Keira tricks her into coming over without revealing that Casey will be there too. When Zoe arrives and is confronted by Casey, she realizes the trouble she's in. Zoe pleads for forgiveness, admitting she got carried away by her attraction to both.
Casey and Keira are skeptical and demand Zoe make amends. Their punishment involves strap-ons, which excite Zoe despite the intended severity. A steamy double-penetration unfolds as Casey and Keira release their pent-up frustration.
Despite the scolding, Zoe is living out her fantasy of being desired by the two sisters. The question remains - can Zoe earn back their trust after the tempting escapade?.