In Witcher 3: Wild Hunt, How To Bed/Have Sex With Keira Metz. The Witcher 3: Wild Hunt is an extremely mature adventure-RPG so, exactly like in the previous chapters of the White Wolf saga, you can bed women you enjoy most during the game. One of the women Geralt sympathizes most on his quest to find Ciri is the witch Keira Metz, an old friend of his who will require something to happen during the game in order to accept the witcher's avances.
First, meet Keira Metz. The first meeting will be pretty… informal, as you will find her half naked in the bathtub.
Then, you will embark in a particular main story quest (we won't provide any detail about it to avoid spoilers on the storyline) and, right at the end of it, you will have an optional objective to complete – she is searching for a magic lamp. If you do it, Keira will remember your good action and will be more comfortable in your company.
Later on, she will ask you to find some ingredients from an abandoned carriage in order to activate the lamp. Then she will organize a romantic dinner in the woods.
There's no need to explain how things will go on from that point but, if you really need it, you can guess from this screenshot what happens next.