Her Yoga Teacher's Assistant

The picture showed Nathan everything he needed to know. By now the two were at the building where she took her classes, standing behind a group of fourteen other class members, all women of varying age groups dressed in tight, body-framing clothing. Behind them, the class teacher grinned, flashing a thumbs up to the camera, who only he had seemed to notice the two figures posing for.

Nathan tried to avoid looking at the center of the image, tried to set the phone down, yet he couldn't. He couldn't look away, and it wasn't just his eyes being drawn to Jenna's sweat-coated form, her features practically visible in their entirety through the thin, tight booty shorts and hot-pink sports bra. Her breasts jutted out from between two squeezing arms, her fingers on either side of her face in a peace sign. Her cleavage was visible out of a large boob window in the "shirt's" material, a sort of wider neck-line that stretched down almost to the front of her breasts and showed both more and less than he wanted it to.

The gap between Jenna's clothes exposed her rock-hard stomach, her beautiful abs, though not the most chiseled, still shone beautifully with sweat. Her thighs and legs were drenched too, and though he noted an odd, erotic excess of liquid staining the area around the crotch of her shorts, her slender, soft legs were placed one behind the other in a dainty, almost mocking way, hiding any further detail of her crotch, yet showing off the slight exposed ass her scrunched-up, already excessively short pants.

Normally, he'd be drooling over her, probably masturbating too, but now his throat was dry and, despite his raging erection, her body wasn't all that aroused him, and it certainly wasn't what made him wish, possibly for the first time ever, that she was wearing more clothes.

A familiar, tall, well-built man stood beside her, one arm reaching out to take the picture, the other wrapped around her waist groping her ass, which she seemed to enjoy judging by the face she was making, an only half-purposeful wink and a struggling smile that looked as though he might have even spanked her before posing. The assistant stood at what Nathan recalled being about six-foot-seven, and only now was the half-panicking, half-aroused boyfriend noticing the impressive bulge in his tight pants that Nathan was sure had to be fully erect, yet somehow doubted that it was.

The assistant's dark brown skin contrasted against his light blue eyes and dyed black and blue hair, and his own sweat glistened along his muscular body, though not as prevalently or heavily as Jenna's. In any other circumstance Nathan might have admitted he was attractive, but here, standing with an arm around his own girlfriend's ass, and the smug, horrible look on his face?

They looked like the hottest, most perfect couple Nathan had ever seen.

Staring at the screen for what felt like hours, Nathan slowly realized he needed to send something, although he worried she may not get it until after class. Though at the same time, he relished the strange, borderline masochistic feeling of not knowing what she might do if he didn't try to stop them. Then, he pondered the idea of actually giving them some sort of permission to do whatever They had planned, not that it looked like they needed any. Finally, he thought about simply asking to hear about it afterwards, being drawn to the allure of his girlfriend having had sex with another man, only hearing afterwards what they could have done, being left to wonder on his own in lustful agony...

Before he could send a message, however, Jenna sent another text;

"Class starting now, me and Sammy haven't done anything together yet, but as you probs guessed he's been the reason I've been staying late, along with hanging out with other friends too. Leaving early is just me planning bad tho lmao"

Finding the tension slightly broken, Nathan let out a sigh first, then a chuckle at his girlfriend's usual personality still shining through, teasing him even in this situation.

Hesitant, he pondered over the word "yet," his mind racing with possibilities of what they could do if he just gave them permission, if that was even what Jenna was fishing for.

Then Nathan's mind snapped back to reality. His girlfriend's been "hanging out" with this Sammy guy for ages, and now they've sent this weird, lewd selfie to him. He should be mad, angry that his girlfriend's been off flirting with some other guy, and yet...

He thought back to how aroused he had just been, imagining what his girlfriend could have been doing without him, and he paused, thinking the decision over carefully. They'd already done tons of other lewd stuff together, even if some was just to supplement him admittedly not being the best in bed. What made Jenna having a fuck-buddy any different than the other kinks they'd tried out? Hell, it may even just be a one-night stand...