Q: Delete books from iCloud?

Hello rainbowcat5,

Thank you for using Apple Support Communities. 

I understand from your post that you would like to delete your books from iCloud. I know keeping your iCloud account organized is very important.

To remove a book from iCloud, tap Settings then iCloud. Then tap Storage and Manage Storage. 

Under Documents & Data tap iBooks. 

Tap Edit in the upper right corner of page. 

Then tap the red circle to the left of each book you want to delete or tap Delete All at the bottom of the page. 

Alternatively, you can also delete the books directly from the iBooks app as shown in this article: 

Delete books and audiobooks

Remove books or audiobooks from the iBooks app using the steps below:

1. In the upper-right corner, tap Select.
2. Tap the books you want to delete. 
3. Tap Delete.
4. Tap Delete This Copy.

Best Regards