I just finished my first book. 「最後の詩集」 is collection of poems. Only 80 pages but it has a lot of poetic language and more obscure words I've never heard of. For example, names of plants that I've never heard of, like 「エニシダ」. I've had the book for 5 months, I've recently started reading it again. It was too difficult when I first got it, I didn't understand any of it. I can read most of it now, I really enjoy it.