Eva had opted to sit on the "near" side of Charlene, so I didn't have any trouble making out the cleft of her sex amid the dark blond curls of her pubic area. At the top, the hood over her clitoris was barely visible; her labia were thin and the area between them appeared to already be glistening faintly. It took only a few moments for Charlene to get herself seated on the floor between Sis' feet. Again, their positions ensured that I had a good view of what was happening as Charlene initially contented herself with simply leaning forward and just looking at Sis. After just a couple of minutes, I heard Eva tell Charlene "Go ahead and touch me, if you want to — it's only fair."

With that, Charlene slowly moved her hand between Sis' legs… and after a brief hesitation, made contact with Eva's mons. The sight as Charlene's slender fingers tenderly probed and manipulated Eva's womanhood soon had me sporting what I was sure was the biggest and hardest erection I'd ever had; it was only a couple of seconds effort to free it from my pants and underwear and begin stroking myself as I kept my eyes locked on the sight before me. Charlene whispered something I couldn't hear to Sis and got a nod in reply; it was when I saw the ends of her fingers gently ease toward Evas opening that I couldn't hold back any longer, and sprayed the wall of my closet with what felt like quarts of my cum.

Even as that was happening, however, I had my eye glued to my viewport into Evas room, and was able to see that even though Charlene barely had the first digit of a single finger through the portal to Evas sex, it was enough to have Sis' breasts visibly hard and tight, and her nipples erect — as well as thoroughly anointing the invading digit with her female essence.

It wasn't just Eva that was feeling the effects of Charlene's manipulations: it was plain as could be (even from where I sat) that Charlenes breasts were tight and sporting hard and erect nipples, too. With her sitting at an angle to me, I couldn't see what was going on with her extra appendage, but the fact that Sis made several lengthy looks that direction suggested pretty strongly to me that something was happening with it.