There were a lot of things they left out when they told their story.
The sex was one of these things.
After Ron had returned to them, all those months ago there had been a palpable tension hanging heavily in the air, almost choking them.
Comfortable silences changed into tense ones, the implication of sex clung to the atmosphere like smoke and it only took one movement, one touch and everything broke. Everything became teeth and hands and lips and moans. It was Harry's darkening green eyes and Ron's lean limbs and Hermione's soft panting.
It was best left unsaid.