Doesn't mean I have already ****** my sister-in-law, just that the feeling comes and goes. It goes away if I don't see her in a long while and comes back if I see her physically, the stronger the more I see of her. It's purely physical, as she has a somewhat difficult character and I couldn't imagine sharing my whole life with her.

I'm talking about my wife's older sister. She's four year older than my wife, slimmer and prettier of the two and has bigger boobs. My wife is busty too, but her sister's boobs are even bigger. At least at some point she wore a 75E/34DD bra. I know this because I have taken a look at my sister-in-law's bra while she was changing and also because I have heard the two sister discuss their bra sizes.

I don't remember how long I have wanted to **** her. I certainly liked what I saw the first time I set my eyes on her. During the first years with my wife, her sister even seemed to flirt with me a bit. Both my wife and their mother have suspected that she once had some kind of crush on me.

The first incident that started a serious obsession for my sister-in-law happened about three years ago. We were at the sisters' parent's house for the New Year. At some point my sister-in-law told she was going to take a shower as the rest of us stayed sitting in my in-laws' living room. A couple of minutes later I was feeling thirsty and went to the kitchen. Upon entering the kitchen, I clearly hear the sound of the running shower, and suddenly realised both the door between the kitchen and the changing room and the door between the changing room and the bathroom were wide open and I could see my sister-in-law completely naked standing under the shower water running over her huge boobs. Her breasts looked just as perfect as I had imagined, nipples pointing slightly upwards. I didn't want to stay and stare, so I just looked at her long enough to store a good mental imagine, then went back to the living room with much trouble trying to hide a starting erection. I have *********** countless times thinking about how my sister-in-law looked naked.

After that incident, I was obsessed with my sister-in-law for a long time, but finally the feeling went away. She's been quite reluctant to leave her home and we haven't had her visit in a long time and I haven't seen her much at the in-laws' either. This week she came to visit us again. The first thing I realised was that she had gained weight. Yes, some in her face, some in her legs and belly, and A LOT in her boobs! No way she fits in an E cup anymore... I have no idea how big as she didn't pack a spare bra I could have studied more closely and I daren't ask directly. There is a heat wave going on so we headed for the beach... I was a little disappointed that she wore a black one-piece swimsuit instead of a bikini, but she made a nice sight nevertheless. In fact the next day I kept thinking about my sister-in-law all day and on the way home I had to stop at some woods, take out my **** and ********** a huge load in the nature.

Perhaps it was wise that I had made that pressure release, as things got even hotter than before. It was another scorching hot evening, so again we headed to the beach. Same boring one-piece swimsuit, but it suddenly got interesting after my sister-in-law had come back from her swim. This time she changed on the beach. She simply lowered the straps of her swimsuit, then pulled a t-shirt on top of that and removed the swimsuit underneath. At that point I realised: OMG, she didn't put on a bra! As you can imagine, putting on a t-shirt on top of huge moist boobs with hard nipples from swimming in somewhat cold water has a certain effect. You could certainly see her boobs clearly swinging about with no support and nipples poking through the moist fabric... Now I again really really want to **** her!
moppister moppister
31-35, M
2 Responses Jul 10, 2010

I had a crazy exciting day with my SIL at our in-law's place today. Short summary: I walked in on her while she was changing out of her bra and into a bikini, asked her what size she has today (80G / 36G) and spent most of the day looking at her G cup breasts in a bikini top meant for something slighty smaller...

yes, i can understand how you feel. i walked into my sil's room one day ahd saw her standing naked there as she was changing. what a sight! i still remember that till today. and she's got boobs which are so nice and firm and i'm sure an equally good ***** below.