My wife Holly is justifiably proud of the birthday  presents she gives me. We have a pretty plain-vanilla sex life, but once a year  in August she thinks of ways to spice it up a little. It's a tradition that  started when we were first dating, even before we were sleeping together. She  invited me to her apartment for my birthday where she made me dinner, then had  me unwrap my present: A Penthouse magazine. Maybe that doesn't sound like  much, but we spent the rest of the evening cuddled up in her bedroom, reading  the magazine and talking about it. I still think it was a great birthday  present.
          
            For other birthdays we've spent weekends at nudist  resorts, or done some role-playing ("Egyptian slave weekend.") Once, when she was eight months into a  difficult pregnancy and the doctor advised us strongly against  intercourse, she turned the porn filter on the computer off, and let me browse  to my heart's content while she knelt between my legs and gave me a memorable  blow job. Sometimes her birthday present has been more spontaneous "“ like  when we couldn't get out of a work-related banquet, but we happened to notice  the hotel swimming pool, sitting there unused on the other side of the French  doors. We slipped out of the banquet, made our way to the pool area by another  entrance, stripped naked and made love in the spa "“ and made it back to the  banquet before the CEO finished his speech.
          
            One of my fantasies had been threesomes, but Holly never  seemed interested so I didn't force the issue. Then, one birthday, I came  home and Holly's cousin Heidi was helping Holly make dinner. Heidi had just  turned 18 a couple of months before and bears a haunting resemblance to Holly  "“ except her hair is longer, she's a couple of inches taller, her boobs are  perkier, and she's ten years younger. At first I thought Heidi was going to  baby-sit while Holly and I did who-knows-what, and it still didn't dawn on me  even when Holly told me the kids were at grandma's for the night. After  dinner Holly and Heidi went upstairs and in a few minutes they yelled at me to  come up. I was still utterly unsuspecting when I walked into our bedroom to  find the bed neatly turned down, Holly naked and Heidi wearing only a black  thong. "Hi," they said.  "Surprised?" "Uh, yeah!"  I stammered.
          
            "You're getting a threesome for your birthday, but  here's the rules." Holly  explained. "Heidi's pussy is off limits to you. And when you cum, it's  going to have to be with me. OK?" What was I going to do? Argue? This was  by far the most exciting birthday present she'd come up with, and I wasn't  complaining. I don't remember the exact sequence of what happened, but it  involved making out with Heidi while my wife undressed me, and licking  Holly's nipples and then Heidi's nipples, and somehow got around to me  lying naked on the bed while both girls took turns sucking my cock. Then Holly  laid next to me while Heidi continued slurping my joy stick, and when I gasped  "Oh God, I'm gonna cum!"  Heidi backed off and I rushed to slide myself into Holly's tunnel of  love so I could cum in her. After all, a deal's a deal.
          
            Afterwards we lay back on the bed and giggled and watched  TV. It was one of the best birthdays I'd ever had.
          
            Heidi came back the next year for my birthday and pretty  much the same thing happened. But after that, Heidi got a serious boyfriend, a  big guy named Peter, and they got engaged. Heidi didn't show up that year and  while I enjoyed myself at the nudist resort, it wasn't quite as good.
          
            A couple of years went by and one night a couple of days  before my birthday I came home and Heidi was in the kitchen again, helping  Holly make dinner. After we ate, Holly asked if it was OK if I got my birthday  present early that year, and I realized why Heidi was there. This time, though,  we went upstairs and both girls stripped naked "“ no more black thong for  Heidi, and I got to see her young pussy for the first time. Still, it took me a  few minutes to realize that I was going to be permitted to make love to Heidi.
          
            The three of us made out for a while and I inspected  Heidi's pussy like it was my new toy. Finally, with a glance at my wife as if  to ask "Are you sure this is OK?"  I slid my hard cock inside her. We made love for quite a while and finally Heidi  started panting that she was going to cum. I noticed that she panted just like  Holly "“ it must be a family trait. Finally she came and I started shooting  love juice deep inside her young pussy.
          
            The three of us laid back on our bed giggling again, and  I said, "Thank you! That was a great birthday present!" And Heidi said, "No "“ thank you!"  "For what "“ the orgasm?" "No . . ." and then she looked away and  started to cry.
          
            "What's wrong?" I asked.
          
            Then the girls explained. Heidi and Peter had been trying  to get pregnant for a year and a half and it wasn't working. So Heidi decided  to try something else. "We spent weeks figuring out when she'd be the most  fertile," explained Holly, "and  tonight's the night. Heidi may have been our birthday present to you,  but we're hoping you'll give a different kind of present to Holly and  Peter." And I had. 
          Nine months  later, Peter Jr. was born. Heidi showed up for my birthday twice more over the  next four years and we made two more boy babies with May birthdays.  We've agreed that neither Peter nor the kids will ever know that I'm the  real dad. 
          In the meantime I'm looking forward to my next birthday, hoping  it's half as good as the times as the ones I spent with my wife and her  cousin.