No, Alina and Nikolai do not marry in the Shadow and Bone trilogy by Leigh Bardugo.
While they share a strong bond and a deep connection, their relationship is ultimately platonic. Alina's romantic focus lies with Mal, her childhood friend, and Nikolai finds love with Zoya Nazyalensky, a member of the elite Grisha army.
Despite their lack of romantic involvement, Alina and Nikolai remain close allies and friends throughout the series. They work together to defeat the Darkling and protect the world from the threat of the Fold.
Their friendship is a testament to their shared commitment to protecting their world, showcasing a powerful and enduring bond that transcends romantic love.
