The Finnish suffix “-kainen” is used to create nouns that refer to things or beings associated with a particular quality or characteristic. Even though we don’t necessarily mentally associate it with a similar meaning as “-mainen”, it still is. Hence the translation of “bearlike” is close enough.
I did it a little while ago. Was very easy. Download books with kindle app, load them into Calibre and use a one click plugin to strip the DRM. I think this was the step-by-step I used.
https://nerdschalk.com/remove-drm-kindle-books-de-drm/