HI Guys
I have a number of books on my kobo that are kepubs. so once i read them i delete from device but there is still a thumbnail. I could delete but it says delete from library. If i do this does this mean that next time i sync on wifi they get deleted out of my purchase history?

i have back ups of them as always downloaded via ade (now calibre)
the only reason i ask is i like to keep kobo tidy and only keep on there unread and a reread folder