Gf goes to the gym [MFM]

This is a story involving my girlfriend and a time we went to the gym together .One night we decided to go to the gym together to get a workout in since there was nothing else to do and she decided we should get more in shape as of late.
Our gym is one of those 24hr gyms and is typically empty since it isn’t that large or popular. She wore some black yoga pants, a grey sports bra that might have been a little too small, and a zip up track jacket. My gf had big tits so anything she wears shows a lot of cleavage even if she isn’t trying to.
When we arrived at the gym it was fairly empty, more than usual. There was about 5 other people in the gym besides us , two guys who were working out together , a woman who was working out on her own , another guy in a cut-off and the worker. We walked in and were greeted by a worker who didn’t seem so enthused. We looked around as to see where to start our workout and headed towards the treadmills.
In front of the treadmills there was one of those big glass mirrors that covered the whole wall and which allowed us to look at the ourselves and the rest of the gym with our backs turned. My gf took her jacket off and proceeded to do a few stretches before getting on the treadmill. I was able to see the guy in the cut-off checking her out as she bent over for her stretches since he was the only one nearest to us . She finished and had proceeded to get on the treadmill I had already started running and was well into my workout when she started . She started with a slow walk and slowly went into a jogging pace.
Her tits were bouncing up and down with every step as she increased in step. The guy in the cut-off sleeves was using one of the machines in which the direction he was facing was towards us so he was getting quite the show from my gf. As she ran her sports bra would slip down a little revealing her areolas little by little. I was getting turned on watching her bounce as she ran and I know the guy in the cut-off was too since he couldn’t seem to keep his eyes off.
When we finished the treadmills she hopped off with one of her nipples clearly visible and out. The other covered but still noticeable since it was hard for some reason. The worker seemed to notice and fixed himself to sneak looks towards our direction in a way so we wouldn’t notice him. She nonchalantly walked towards a machine she wanted to use and kept working out with her nipple out. I went to get a drink at the water fountain at the other end.
The guy with the cut-off sleeves moved to a machine closer to my gf and struck up a conversation. I walked back towards them and was engaged immediately in conversation
“Hey babe this is Adam he was just showing me how to adjust my technique so I can get a better workout” my Gf said do me as I approached
“Yea her form was a little off but she got the hang of it now” he said as he faced me but kept sneaking looks at her tits
I then asked him if he could spot me on the bench since my gf went off to do squats and probably couldn’t have done it to begin with.
“I don’t mean to upset you but your girls hot” Adam said to me “Yea i get that a lot , she likes to show off a little sometimes haha” I replied We finished and I went toward my gf who was getting ready to leave. “Thanks for the tips Adam , hope we run Into you again sometime ” she said in a flirty way “No problem and you too I wouldn’t mind that at all” he said We all then headed out toward the door which made it a little awkward since we thought he was staying to finish his workout . It turns out as we walked to the fairly empty parking lot that we parked next to each other .
My gf kept talking to him as we walked I got to my side of the car and hopped in . My gf spontaneously put her hand on his crotch area before opening her door. He immediately closed the door as to not let her in . She dropped to her knees and pulled down his shorts. Since it was so late she didn’t care if anyone saw and chances are no one was going to since it was pretty empty and there wasn’t a big street nearby .
His cock fell out and she took it into her mouth . By this time I was out of the car and I opened the back door to cover a little and he opened his door as to sit down . The sight of my Gf’s random act of sluttiness turned me on. She bobbed her head up and down and looked at him in the eyes then me and back and forth .
“You like that ” she said as she stopped and jerked him off
“Hell yea keep going” he said as he grabbed her head and pushed it .
“I have a better idea ” she said as she opened the back door his car
“Get on the other side” she said He walked over and opened the other side of the door .
He sat down at the end and she bent over and continued to suck his cock . She worked on it moving her head up and down deep throating. She was enjoying her self. She slipped her pants down a little and pulled me toward her. I inserted my cock and proceeded to do her from the back. She was extremely wet and was getting into it .
This continued on for about 5 more minutes until Adam interrupted
“I’m gonna cum I’m gonna cum” he said in pure pleasure barely able to get the words out. She the started to go harder licking and sucking and stroking all while taking it from the back.
“Yes cum for me, I want this big cock to cum for me” she said in intervals as she was taking me from the back. Without notice Adam came all over her face . She then put his whole cock in her mouth and kept going cleaning up whatever was left on his cock.
She got up and smiled at home and then at me “Well that was a lot, thanks for the workout tips” she said as she opened her door and hopped into our car.
He sat there confused as to what had gone down I also hopped in the car and closed the door. She looked at me and then started to suck my cock as I sat in the drivers seat. She did this the whole ride back to my place. I came in her mouth as we arrived and she was pleased with what she had done she smirked got out the car and headed inside after her long workout .