I don't think the Manual called Furniture-mancy Manual is functioning correctly. As says several other reports it seems, the one that removes one level and should change the theme. If not already done, it would be nice if it could be removed from the drop tables. Until it can be fixed.
Character I have it on is Mathan Jarshall.
Few other reports.
http://www.efupw.com/forums/forum/main-forums/bug-reports/85741-furniture-mancy-manual
http://www.efupw.com/forums/forum/main-forums/bug-reports/74845-furniture-mancy-manual-not-working
http://www.efupw.com/forums/forum/main-forums/bug-reports/42628-permanent-summoning-theme-down-a-level
http://www.efupw.com/forums/forum/main-forums/bug-reports/42034-furniture-mancy-manual
Just would be nice not to stumble upon it in trades and such.
Report where they are found as well if you find them and they do not work. In case this is issue for specific ones, it will not help if we have fixed the base version.
I got it from trade, so sadly I don't know where it was dropped. If I see the player in game again I'll try asking.
They come from the Civil Service quest.
New ones that drop should be fixed.
If you have an old one, just trash it and and assume it was all rotten and worthless.