[FFM] lost a bet

It started with a lost bet. We were looking for a unicorn. We tried the usual, Tinder, Craigslist, Reddit and found no match, until my wife, Becky, told me that she will found her. I was very doubtful and challenged her. We agreed over the prize for the winner: if she found one before the end of the month, I will have to be her sub for one day, otherwise I would she would be mine. The day to be determined by the winner.
At the last day of the month she had found Lacy… a very sexy women that fit our standards. She was nice, sexy and cheerful, with the sexiest ass you could imagine.
That night, we were waiting Lacy to come to our place. Becky handed me a glass of wine and a small present. It was a small box closed by a red ribbon. She pressed me to open it. I opened the box and found a nice leather collar with a little lock on it. I was very not sure of the purpose and her motive. As she remembered my lost bet, she gently close the collar on my neck and locked it. I started to worry that the night I expected would differ from my expectation. I understood very quickly when she grab me by the collar and request me to be fully undressed before our guest came in. I fulfilled her order very quickly. She drag me by the hand and point the armchair. I understood that she wanted me to be sited, and I complied. She look very pleased to look at myself completely nude, except for my leather collar. Becky lean toward me and told me very close to my ear: Now you behave or you fuck no one tonight. I was so aroused by her, that I put my hand on her inner tight, Becky than slap my face and told me that is your last warning! Now fucking behave!
I think I was save by the ring bell, as Becky was going to give me a second, we were interrupted by the doorbell.
Becky came back with Lacy. She was very hot in her sexy red dress. At first sight Lacy was very doubtful about seing someone at the first time…naked. Becky invite Lacy to sit on the couch, next to her. She quickly explained the situation and make sure she understand the role play here. Lacy was very excited, the young blond women stated that she was attracted mainly by my wife than me… well that sucks, but anyway… they started to make themselves confortable, started to chat, the first time tried to join the conversation, Becky quickly reminded me that I should shut the fuck, if I wanted to be fucked.
After many women talk and flirt and cocktail that I done for the lady, they started to have some fun. I was quietly watching them kissing, undressing and eventually fingering and pussy eating. They gave a really good show, I was starting to join her and fuck the first pussy I would get.
My wife come by me, she was all sweaty, she lean close to me and whisper in my hear: I am going to suck you, if you don’t come after 1 min I am going to let you fuck her tight pussy.
Then she put her iPhone with a 1 min timer and start to give me the bj of my life. While she suck my dick, Lacy come in my back, she pressed her boobs on my back, and started to hold my arm on the armchair while she licked my neck and my hear.