Requests can be made by the author if they simply want their book removed.
Requests can also be made by readers if the book doesn't meet one of these requirements:* Book is no longer available as a giveaway (was not permafree).* Book is just a preview and not the full manuscript.* Book contents have nothing to do with the description.* Book has adult themes, but had no warning in the description (won't be removed, but a warning will be added).
You can also elect to list another reason instead, and I will determine whether or not it should be removed for that reason.