For fans, sexy, female-centered entertainment is a welcome escape from reality

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When it was released in late January, Onyx Storm – the third book in Rebecca Yarros’s The Empyrean series – became the fastest selling adult novel in 20 years. It sold more than 2.7m copies in its first week, according to the New York Times. Across the US, fans lined up in the cold outside of Target stores to nab special edition copies. In the UK, there were midnight-release parties where attendees wore costumes, made friendship bracelets and applied dragon-themed temporary tattoos.

The Empyrean series is a prime example of romantasy – a genre that blends high fantasy and romance. It follows the cadet Violet Sorrengail as she trains to be a dragon rider. Fast-paced and detailed, the books boast mythical creatures and magic. There’s also a lot of sex. On more than one occasion, sturdy wooden furniture is broken during vigorous bouts of lovemaking. Violet climaxes every time with her generous lover, Xaden. Violet and Xaden’s dragons are mates – and they have sex too.