Girlfriend brings up cuckolding [cuck’s perspective]

A few months ago after having sex with my gf we start to talk. She seemed very unsatisfied and she ask me how do I feel about opening up in the bedroom. I asked her what she meant and she suggested bringing another person in the bedroom. I asked her who and she said another guy. I wasn’t too enthusiastic about the proposal but she was persistent and told me how happy it would make her. I gave into her and agreed. I want to make her happy. The next day while at work she texted me and told me she found someone. I was surprised how fast she found someone. I told her cool and when was it going to happen. She said that night. I knew she had to be talking to this guy for a while but whatever I agreed. The more I thought about it, I started to get excited.

I get home that night and she tells me the guy is on his way. I asked who it was and she said it was a coworker. Now I for sure know that they probably had been flirting for a while and some tension has been building up but I don’t say anything. He gets to the house and he is a very good looking tall dude kinda the opposite of me. We are chilling on the couch having some drinks and actually having a pleasant time. I went to the kitchen to fill up more drinks with my gf and asked the plan. She asked if it’s ok to sit on his lap and start. I said yes. We get back to living room and she sits on his lap. Not gonna lie, I was getting turned on seeing her like this.

We all down our drinks and right when she’s done she starts making out with him. This made me rock hard. She is straddling him making out while he grips her ass. I never thought I would enjoy it this much. She hops off and strips naked. She is looking so sexy. I got up and tried to feel on her but she slaps my hands away and told me sit and watch. Her dominance turned me on even more. She then unzips his pants and pulls out his monster cock and starts sucking. His cock was way bigger than mine. She was sucking him like a pornstar. She was enjoying it so much and so was he. She would even slap her face with it as she looked at me with a devilish grin. She was looking so sexy with him. Then she hops on his dick and started riding him. Her pussy was so creamy as she bounced on him. I never heard her moan like this before. She came multiple times. She then tells him she wants him to cum in his mouth so she hops off and goes back to sucking him until he explodes in her mouth. She sucked the life out of him. He looked beyond satisfied. She then come over to me and starts to suck my dick. She was hungry for more cum. It was the best bj I’ve ever gotten from her. I lasted less than 5 minutes and she drank every last drop from me. It was one of the hottest experiences I’ve had. Then they both head to the bedroom and she told me I can sleep on the couch. They would end up fucking again as she left the door wide open to make sure I can hear.