We were of legal age when the sex began...
We are a large family. My father had four sisters and three brothers, my mother three of each. That meant a lot of cousins. My twin cousins Christine and Susan were my mother's youngest brother's girls. They lived eighteen miles away from us in a little English village called Harcourt, on the south coast. Back in the early 1970s, a distance like that was significant. We had one car, which dad used solely for work and family outings, one phone which we weren't allowed to use, and they lived off the main bus routes on a dirt track that bicycles ventured down at their peril. So we hardly saw them as we grew up.
I remember someone's birthday party in the local church hall, about 1974 or so, and Chrissy and Sue were there.
Even though they were twins, Chrissy was a little shorter and a fair bit plumper than Sue, and she had darker hair. As is often the case with girls, being plumper meant she also got breasts earlier, and later as a grown woman, larger than her skinny sister. I think it was the first time I realised boys and girls grew differently.
I joined the Army just days after my eighteenth birthday and was training as a transport driver. At home on my first leave, after only having had my licence for three days, my father lent me the car. Another cousin had organised a surprise party for Christine and Susan's eighteenth birthday, at the Prince of Wales Hotel in Harcourt. Probably not really a surprise, in hindsight.
I drove cousins Willy and Jennifer to the festivities. The party was under way by the time we arrived. Chrissy and Sue were already quite tipsy.
Susan wore a flowing yellow dress that hugged her torso then billowed out to below her knees. Christine was in a white cotton minidress - sort of tight bodice and miniskirt in one. It didn't hug her form, but there was no mistaking she was all grown up now.
There was the usual raucous laughter and shenanigans that went on for hours. Susan was snogging away in a corner with a local boy, captain of the rugby team, athletic build, well-dressed - you get the picture. Chrissy looked less than pleased with the party. I was dancing with her, and leaned in to ask her why she had a long face.
"That's Ronnie Wainwright my sister is snogging. She met him through me. On a date."
I saw the problem. Her sister had stolen her date. The song ended and we sat down.
"Um, had you and Ronnie been going out long?"
"No, first date. She didn't know it was a date, but still..."
"Yeah. Look, forget him. If he did that to you he'll do it to her when the next pretty face comes along. He's a dick."
"Maybe. I was kinda hoping he'd be my first dick though."
Girls didn't usually talk like that in the '70s. I was shocked.
"Oh. Sorry." She said. "Bit tipsy. Bet you get plenty in the Army though, right?"
I blushed. "Um, no, not yet at least! Jeez Chrissy! You're a funny girl."
"Yeah. Right. The fat ones are always funny..."
"What? No I didn't mean... You're not fat Chrissy."
I didn't know how to handle this. I was an eighteen-year-old squaddie, not a relationship counsellor.
"You think I'm pretty Steve?"
"Yeah. I always thought you were."
"Rubbish. When?"
"Um, OK. Since you were the first of my cousins to get boobs!"
Then she laughed. "Oh I see. Typical boy. Thinking with your dick."
I laughed, then stopped as I felt her hand on my cock. I looked around nervously. Nobody was going to be able to see. My cousin looked straight ahead as if nothing was happening, except of course something was: My cock rose fast into her grasp.
"Ooo Stevie! Maybe you do think I'm pretty. I'm flattered. Follow me. I'm gonna give you a birthday present - on MY birthday."
I knew she was my cousin and probably a bit drunk. I didn't care. I followed her out into the laneway next to the pub, she held my hand and took me around the back and into an old stable there. The inside was bathed in the glow of a streetlamp - not glaring, but enough to see clearly.