Soulless

Soulless is the first book in The Parasol Protectorate series and introduces the main characters and world. While each book has a self-contained mystery, the overarching character development and relationships build across the series, making it best to start with Soulless.

Soulless is the foundational novel for Gail Carriger's Parasolverse, a shared universe that includes several interconnected series and standalone novels. Characters and events from Soulless often appear or are referenced in her other works set in this world, such as the Finishing School series and the Custard Protocol series.

Yes. Yen Press published Soulless: The Manga, adapting the first three Parasol Protectorate novels with art by Rem. Volume 1 came out in March 2012 and is a separate book from the novel.