Suggest some public stimulation.

"Hey," you say, a fun idea popping into your head. "If you want to get more comfortable talking about sex, I've got an idea for something that might help you practice."

Heather's eyes widen a little behind her glasses; she looks worried, but intrigued. "What'd you have in mind?"

You open your mouth to explain, then think better of it. "You up for trusting me a little?" you say instead with a mischievous smirk.

Heather's eyes roll, though her grin doesn't fade. "I mean, I guess I'll give it a shot."

That's all you need. Taking your fingers off her pussy—you're pleased to see her buck her hips a little as you do, biting her lip again—you beckon her to follow you. Turning to head back toward the front of the bookstore, you lead the way toward the cafe counter, near the entrance. Right now, the place is fairly busy. You notice several people's eyes on Heather as she follows behind you; most of the looks are unsurprised, many are admiring.

Before the cafe counter lies a small lounge, a couple of tables and several plush armchairs and sofas. Customers relax with new (or yet unpurchased) books, sipping on coffees and teas and munching croissants and muffins. Beckoning to Heather once again, you gesture to the handrail dividing the lounge area from the book checkout lines. "Lean back on this."

Heather glances uncertainly toward the service counter. "Shouldn't we order something if we're gonna hang out?"

"Nah, don't worry," you say confidently. "This'll be good for their business." Heather looks a little nervous at that, but takes the spot you suggest, leaning back to support herself against the railing with her hands. You draw a couple of curious glances from the people at the nearby tables, but no one seems to pay you much attention.

Smiling, you move to stand in front of Heather, facing her. Reaching between her legs again, you insert a pair of fingers inside her still-wet pussy this time, while also bringing your thumb to her clit. Heather's eyes widen as she lets out a gasp, then immediately bites down on her lip, eyes darting around at the nearby customers. Again, apart from some brief glances, a few coming with appreciative smiles this time, no one seems that bothered.

"Relax," you urge her as you begin to work your fingers in and out of her slick tunnel and rub her buzzer. "See? It's okay. No one minds."

Still biting her lip, Heather nods. Her face looks red enough to catch fire.

"Hey. Stop." Gently murmuring the words, you reach up with your free hand to softly brush her bottom lip, tugging it down and free of her teeth. "C'mon. Let it out."

With one last glance around at the people nearby, Heather's eyes flutter, and she lets out a soft but audible moan of pleasure. Only a couple of customers nearby are able to hear it over the bustle, but now they do turn their gazes to watch, lowering books and drinks.

"There you go," you say with an encouraging smile. "That feels good, doesn't it?"

Heather nods, eyes still shut and mouth still hanging open. "Uh huh...."

"Now I want you to do something for me," you explain. "I want you to describe to me, in detail, everything that you're feeling in every part of your body. As soon as you notice it, just say it however it comes to mind, alright?"

She manages to open her eyes and meet your gaze for a moment, offering a hasty nod before the pleasure overwhelms her again. When she's silent, you realize she needs a further push. "Okay, go."

"It...it feels...." She takes a deep, shuddering breath. "Your fingers are stretching my insides. I can feel my pussy clenching around them. My clit's ti—...tingling and throbbing and, and it feels so good every time you rub it. My thighs are shaking...oh fuck, I can feel my ass jiggling 'cause of how they move...I'm tensing it now, feeling how heavy and bouncy it is...."

"Good," you urge her on. "What else?"

"My...toes are curling," Heather pants, breaths coming hard, little moans slipping out with each. "I feel shivers running all the way down my legs, up my back...my n-nipples are so hard, my sweater's all scratchy against them and I love how it rubs...fuck, my skin feels so tingly and sensitive all over, oh God, I wanna cum now, I'm so close, I don't care who sees, I don't care, I just wanna feel good, I want it...."

"Good, Heather," you murmur. "Now in a second, you're gonna cum, okay?"

"Yes, please," she gasps, totally past the point of attending to her surroundings. "I want it, I wanna feel my pussy squeeze around your fingers, I want my clit to make me feel good, I wanna get off like a horny slut...."

"Okay," you agree, "but when you do, I want you to do something else for me, okay? Look me in the eyes and stick out your tongue, while you're cumming. You can close your eyes partway, but not completely, okay? Keep looking at me."

"Uh huh," Heather replies wordlessly, grinding her hips against your hand. "Uh huh...."

"Alright." You give one last nod. "Whenever you're ready. Cum."

She lifts her head, wrenches her eyes open fully halfway, opens her mouth, and slides her tongue out to hang over her bottom lip down to her chin. All restraint crumbling, she lets out a loud, drawn-out groan of animal release. Her inner walls contract and clench as if to trap your fingers as a powerful orgasm rocks her.

You don't let up, continuing to rub her clit and massage her G-spot while she continues to groan and shake. Determined to follow your instructions, she holds your gaze through lidded eyes and keeps her tongue out while moaning her ecstasy, a perfect ahegao. Such a slutty, blissed-out expression on her geeky-cute face is the stuff of nerd wet dreams.