There's only so many positions accessible in a shower. On the ground, like Rey wisely pointed out, will at least minimize the chance the chance of injury. The way things have been going lately, he doesn't trust fate not to put one of them in a medbay if they get too adventurous.

Han presses his back to the far wall and lets himself slide down the metal, slightly warmed by the water. He sits cross-legged and she may or may not have noticed that he's already aroused. He's virile and still pretty young - it doesn't take much more than suggestion to inspire him for sex and he had started feeling motivated around the time she got naked.

"I'm all for sexcapades that don't end with one of us in traction."