Sharing pics leads to mutual masturbation over text

In my 20s I worked in a restaurant with a cute sexy blonde with amazing runner's legs, a great body, and a devilish smile. I was a skinny nerd as a young man, and considered her well out of my league. She was in a relationship with the cool, self-assured bartender, and the three of us were friends. Once when they went on holiday they asked me to housesit. One night when I was horny, I opened her underwear drawer, found a black thong, and pictured her tight shapely ass in it while I rubbed my cock on it, and masturbated.

Fast forward 20 years - we've all moved on to different careers, and she and the bartender have long since gone their separate ways. I was freshly out of a relationship and started hitting the gym hard (as many middle-age men predictably do after a breakup). I'd post gym selfies on my socials, and she was among the ppl hitting the LIKE button. One day she slid into my DMs to ask me how life was going and catch up. She was considering ending an unhappy relationship she didn't think was going to work out. Having just gone thru a breakup, I sympathized. We chatted for a bit, and she seemed flirty, telling me the gym seemed to be working and that I was looking in great shape. I thanked her and told her I had shirtless pics I wasn't brave enough to post publicly where family and co-workers would see them, and would she mind if I shared them? "Please do! :-)" she replied.

We both pretended this was me sharing fitness progress and self-improvement pics, but I think we both knew they were thirst traps. 

I sent her a couple mirror selfies in my gym shorts, and when those were met with lots of enthusiasm, I sent her one in my boxer briefs. She said something like, "You'd better not take anything more off, or I'll get too worked up lol." We laughed and wished each other well and went back to our respective days. 

But we'd text every week or so and she'd ask if I had any new pics to share. I'd send pics, and she'd say stuff like how she hoped I was making someone happy with this body. At the time I wasn't, and I'd masturbate as we texted (unbeknownst to her), and share incrementally more risqué pics - my bulge more pronounced, or the outline of my cock visible in my boxer briefs. All the while she fed my ego and egged me on. 

One day I shared a head-and-torso photo cropped just above my pubic bone, showing the V of my lower abdominals. It was clearly a cropped nude, and I wrote, "I had to crop this one so it's not NSFW lol." She wrote back, "You're such a tease!" I went for it and said, "Hey, I'm more than happy to share it uncropped if you want lol." 

"Do it," she replied. 

"You're sure I won't get you in trouble at work?" She assured me she was alone, and that she wasn't on the company wifi. "Ok, once I press send, you can't unsee it. Are you sure?" "Definitely," she replied, and then a few moments later, "OMG, my heart is literally pounding." 

I felt the same way. I was electric with sexual energy knowing this friend and crush and lust object of mine from 20 years ago was about to see (was dying to see!) my naked body and half-engorged cock. I uploaded the uncropped full-frontal, my cock hanging low between my thighs. I held my breath and pressed send. 

A beat. 

Another excruciating, delicious beat. 

Then, "Fuck!!! You're huge!"

"Lol, you like it?" 

"Love it! How big is it?" 

"Want me to get a tape measure and find out?"

"Hahaha yes! Show me!"

I ran to a kitchen drawer for a fabric tape measure and took two photos, measuring the length and the girth, and sent them. If I was excited sharing a previously-taken nude photo, I was positively losing it snapping dick pics at her request for her in real time. 

"OMG, is this you right now?" she asked. 

"It is lol." 

"Can I ask you something?"

"Absolutely!"

"Are you ... masturbating?"

Not knowing how she'd react, I gave her the truth: "I am. You?"

"Maybe lol." 

"Fuckkkkk," I wrote. And we off to the races. Within minutes both of us came, her with her hand in her pants in her downtown office, and me furiously stroking, imagining her touching her pussy to images of my cock. 

It was the beginning of a really amazing little fling we had.