Push their pussies together.

You decide the closest thing to fucking them both at the same time with just one cock is to keep them lying top of each other so their pussies would be smushed together. You push Rosa's ass down so that their pussy lips kiss. The girls start to giggle but their giggles turn into moans when they feel the tip of your slick cock nudge between snatches.

"¡Oh Dios!" the twins groan when you shove your cock deeper, rubbing both of their clits.

"You like having a big sausage in your pussy sandwich?" you chuckle while you slowly move your shaft back and forth to rub against the girls' lips and clit.

Luckily the girls moan not at your lame joke but how you are satisfying both of them simultaneously. It may not feel as good as having your cock inside their mouths or their hot, tight cunts but you definitely have no complaints.

Gabi lets out a cry, only to be silenced by her sister's kiss, when she starts to climax. You move your hips a bit faster and that causes Rosa to cum. When both girls finally settle down from their orgasmic bliss you slide your cock out from between their soaking wet pussy lips, causing them to groan in disappointment, only to shove the full length of your cock in one quick stroke into Rosa's cunt. With your hands resting on her ample ass cheeks you begin to pound away, not giving her any respite until you bring her to another orgasm. You then unceremoniously pull out so you can stick your dick into her sister's awaiting pussy and immediately hammer away at it. When you finally bring Gabi to orgasm you switch to her sister and repeat the process of bringing each sister to orgasm.

You may have proven your virility to the girls with the multiple orgasms they have endured you still have your physical limits. You have no idea who's pussy you are fucking when you feel your balls tighten and even though you want to cum inside one of the sisters you want to be generous and share your spunk with both girls. You manage to pull out at the last moment before your cock head spurts out a jets of hot semen that covers the twin's pussies.

"Holy shit," you mutter, stumbling back to survey your work. Rosa rolls off her sister and, with big grins on their beautiful faces, the girls tiredly lie back on the bed with their legs spread out.

"¡Eso fue increíble!" the girls sigh in unison.

"Thanks!" you smile and lie down between them. The girls snuggle against you as you all take a much need rest to recoup.