I had a pretty serious realationship with a girl in high school whose mom was a lesbian. Her mom had divorced her father a few years prior and by the time I began dating her, the "new man of the house" was living there too.
By about the third month that I was dating her, my girlfiend told me that she "had something serious to tell me" and went on to explain the whole situation to me. I was not surprised and I had pretty much pieced it together by then.
Her mom was not terrible looking, but her mom's partner was the classic butch "man of the house type" (she was an electrician by trade, was tall, big boned and acted like a dude). Things got zanier later when the electrician's daughter moved into the basement of the house (she was in her mid twenties and was a lesbian as well) and often had her "partner" over there as well. So at one point I think there were a total of four lesbos living in that house.
I dated this girl for over a year, so everyone eventually let their guard down and put everything out into the open. Day to day life was fairly normal, except when you'd see open signs of affection, hear certain conversations, or when they'd start playing their lesbian games. There were many occasions when after dinner, while doing the dishes, one of them would grab the other's tit or ass (often my girlfriend's) and that set off this childish chain reaction game of grab ass and it became a semi-serious free-for-all of T&A grabbing and girls giggling.
The electrician's daughter was so-so looking, but her partner was actually pretty hot. I used to call my girlfriend "F.D." and she'd always ask, "What's that mean?" Finally I told her it was my abbreviation for "Future Dyke" and told her she probably wouold become one later in life since she seemed so relaxed with all the T&A grabbing and shit.
To top it all off....(I'm not making this shit up!) her mom and partner actually had a cottage just north of Green Bay (and just south of the Door County area) a mile or two from a small town called "Dykesville." No joke! A pure, unintended coincidence, but pretty funny if you think about it.