Orgy.

Frank had the four girls lie back on the sofa and chairs with their legs spread out so he could fuck them like an assembly line. The experimental erectile dysfunction **** gave him an erection that lasted for hours, allowed him to ejaculate multiple times (he had a vasectomy ages ago so he couldn't get the girls pregnant even if they weren't on birth control pills already), and the stamina of a raging beast in heat. After twenty-six years of faithfully fucking the same woman, Frank felt ecstatic that he was fucking four beautiful women around his daughter's age!

Three girls rubbed their reddened cum-leaking pussies, sore from the merciless pounding he gave them, as he fucked the fourth. They didn't complain though as he was an amazing lover -- he made them cum a several times before he finally came in them. They tried different positions and Lindsey even let him take her in the ass.

When Frank came for the last time before finally going flaccid, he was lying on the rug and had the doctor riding him like a cowgirl on an untamed stallion. Katy fell on top of him after her own glorious orgasm subsided.

"That was an amazing first day," Frank chuckled, impressed by the sight of the worn-out girls asleep on the couch.