Sex sequences are not necessarily an important selling factor, though at times they are. It depends upon the book, the characters, the inter-play of relationships which adds to the dimension of sex or loving making. At times, having sex sequences add to the depth of the relationship and brings out the emotional or physical passion that characters exhibit, which in a way could help sell. On the other hand, out of context sex sequenes can be viewed as gawdy embellishments. There answer in the context of the narrative!