So as writer's block has hit me hard with my longer fic Inevitable, I've decided to work on some drabbles. All of these will be under 500 words (if it goes over it's getting its own fic),
Got this idea from an ask I received on tumblr from Catherineflowers29 I changed my original answer a bit as show Jaime seems to prefer she not see him without the hand on.
Cersei entered Jaime's room and his eyes immediately went to her. Without hesitation, he moved to put on his golden hand, as he always did when she came into the room. He refused to ever let her see him with it on.
She wondered what the point even was. Why had she bothered to go through such great lengths to have this hand made for him when the only thing he used it for was to hide his stump? What was the point of him even putting it on anyway? It wasn't as if he ever touched her with it. He'd certainly more than done his best to always avoid using it any when he was with her.
She decided this time she wasn't going to put up with such foolishness. She smirked as she made her way over to Jaime.
She grabbed him and kissed him roughly.
He kissed her back and as things progressed, he removed her underclothes. Before things could progress even further, she grabbed him by his golden hand.
His eyes widened in surprise as she first kissed it, and then made a quick move to bring the golden hand down to her womanhood.
Yes, I'm a tease, but hopefully, Catherineflowers29 will do a better, longer fic involving Cersei incorporating Jaime's golden hand into their sex life.