Shelley and Gerard
When Shelley was 18 she started dating Gerard, even though technically she was still with Jeremy as of the first date (and when she later told him over the phone, "Er, I seem to have met someone else," all he said was, "That's it, then," and she was disappointed that he didn't seem to want to fight to keep her). Gerard was 32 but looked 25 and acted, "on a good day," 15. He did at least have a job, but he was definitely a work-to-live type, and living meant enjoying himself, and since Shelley was aching to escape the bounds of her inhibited upbringing, they were a good match, at least to start with.
For their first date they went to a pub, had a meal and saw a few bands. At one point, while they were smiling at each other across the table, Gerard took her hand and put it on his crotch. She wasn't shocked (thanks to assorted fumblings with Jeremy she at least knew what she was feeling), but nonetheless did not know how to respond. After a few seconds he let go of her hand. She quite fancied him, but didn't want to be too easy, particularly with the age difference.
After the bands they went back to his (so much more convenient than trying to smuggle Jeremy into her room while her father huffed and paced). He left her on the sofa while he got changed. She looked around at the mess. The decor was predominantly brown and the furniture was a mixture of quality (which she briefly wondered if he'd acquired "off the back of a truck") and scuffed junk, but it suggested comfort, and was a good contrast to her parents' house, where everything looked like it belonged in a museum.
Gerard returned wearing a dressing gown and y-fronts. She was aware of the y-fronts because he'd left the dressing gown hanging open. She managed not to look disturbed, or to laugh. He was carrying something, a brown tube thing. She didn't want to show her ignorance by asking what it was, so she sat back and waited to see what he'd do with it. It became clear it was for drug use, although it would be the next day before she learned it was called a bong.
So Gerard had a couple of cones (mental note, mental note) and they cuddled up to watch music videos. Midnight approached and she knew she should ring her folks to let them know she was okay, but Gerard had fallen asleep with his legs over her legs and she couldn't reach the phone, so she just didn't bother.
At 2 or 3am they went to bed properly. She wasn't a virgin, fortunately, or she would have been miserable as well as bored. She realised he was getting off on having snagged an 18-year-old, and was happy for him to have his bit of fun, but it went on and on and on, and he refused to come inside her (something she was obsessed with, since Jeremy hadn't done it either), even though she really truly was on the pill and wouldn't have risked getting pregnant for anything. So eventually he stopped trying to shag her brains out and they got dressed and he drove her home.
And of course her parents were screaming blue murder. What did she expect? It was only the second time in her whole life that she'd stayed out all night without telling them beforehand, but she was their sole offspring and they were a bit older and all protective and such. So she bore the lectures and the reprimands and later, when they'd calmed down, informed them that she'd broken up with Jeremy (although she hadn't yet, at that point, officially) and would now be dating Gerard. They hadn't much liked Jeremy, but at least he was close to her age. They definitely didn't like the idea of their precious girl being with someone so much older. Shelley figured they'd either get used to it or she'd just move out, and then it wouldn't matter what they thought.