In Lords of the Sith, the Emperor and Darth Vader become stranded on Ryloth and have to rely on each other to get off the planet and survive the insurgents fighting the Empire. Moff Delian Mors is an Imperial officer in the book (because I’ve seen confusion, remember, Moff is a title). She apparently has a key role, and she happens to be a lesbian. Kemp didn’t make that decision to make a statement, it was just natural. Bryan Young discussed the character with Shelly Shapiro, editor of Star Wars books at Del Rey, for the Full of Sith podcast and she has a great and simple explanation regarding the introduction of a LGBT character:
“This is certainly the first character in canon. But there was a gay Mandalorian couple, so it’s not brand new. It’s not something I really think about, it just makes sense. There’s a lot of diversity–there should be diversity in Star Wars. You have all these different species and it would be silly to not also recognize that there’s a lot of diversity in humans. If there’s any message at all, it’s simply that Star Wars is as diverse (or more so because they have alien species) as humanity is in real life and we don’t want to pretend it’s not. It just felt perfectly natural.”