White Nights by Fyodor Dostoevsky

White Nights (1848, approximately 112 pages) is a novella by the Russian author Fyodor Dostoevsky. From Goodreads:

"Set in St. Petersburg, it is the story of a young man fighting his inner restlessness. A light and tender narrative, it delves into the torment and guilt of unrequited love. Both protagonists suffer from a deep sense of alienation that initially brings them together. A blend of romanticism and realism, the story appeals gently to the senses and feelings."

There are multiple copies available at the Stockholm public library. Note that there is already a fairly long queue so I would reserve it early if you're planning on borrowing it (apparently this book has been popular on social media recently). There is also a free ebook on Project Gutenberg.