Alpha takes a turn.

"Well," you say, hesitantly, "usually the woman will, um, move her lips up and down ... you know, to stimulate his ..."

"Of course," Alpha says. "If I may?"

In response, Beta lets your cock drop out of her mouth (to your disappointment), stands up and steps back. Alpha, then (to your gratification) kneels before you. Without preamble, she takes the base of your cock in her hand, leans over your lap, and closes her lips around the head of your shaft. Before the first moan has fully escaped your throat, she starts to bob her head, slow and steady, taking most of your length into her mouth on the way down, and retreating all the way to your tip on the way back.

You draw a long, shuddering breath, and lean back into the couch. Her movements are almost mechanical in regularity, but you are quite ready to overlook any lack of imagination in her technique. A rush of pleasure runs through you every time her mouth takes its trip down over your cock, and the steady pressure of her hand around your base, just above your balls, is a constant little thrill.

“Will you come now?” Beta asks.

It’s a nice thought, but it feels like your orgasm is taking its time arriving, and you’re certainly in no rush to have this particular experiment come to an end. “N-not yet,” you stammer.

Beta glances at Gamma. “We had heard that some men reach orgasm very quickly.”

Gamma nods. “Yes, but we’ve also heard that the ability to sustain prolonged sexual activity is a desirable characteristic in males.”

“Indeed,” Beta replies. “It appears we have selected the correct subject. I’m curious to see how he will respond to the next experiment.”

During this entire exchange, Alpha has continued to caress you with her lips and tongue, not varying her rhythm in the slightest. You have no idea what Beta means by “the next experiment”, but if it’s anything like this one, you’re looking forward to assisting.

Your body heat rises as Alpha’s mouth strokes you. You feel yourself sweating; you hear yourself panting. You think if she took you just half an inch deeper, just once, or just gave you a little squeeze with her hand, it would trigger the “final result” the triplets are looking for, but she stays the course, and your arousal continues to build, and build.