I was 18 (classy gay, I know). I did it with a guy I had been talking to for over a year. We had been teasing the idea for a while (we almost did it once but my mom came home #OOP) but I honestly didn't think it'd go down the day that we did it.
He first invited to go eat, so I joined him. He then said if I wanted to hang out for a bit before work at his aunts house cause they were on a trip and he was asked to house sit while they were gone. We got there, and it was innocent at first. We just stayed on the couch, watching TV. We started cuddling... then kissing... then making out and next thing I know, we're both naked. He knew I hadn't done it before so he asked "Are you sure?" and I said "Yes." So he carried me upstairs and we did the deed on his cousins bed (#OOP). We did it again like an hour and half later on the family couch (double #OOP).