Turned up book I study for characters showing feeling (8)
I believe the answer is:
emoticon
'characters showing feeling' is the definition.
'emoticon' can be an answer for 'characters' (I have seen 'Moody characters' mean 'emoticon' so perhaps 'characters' could also mean 'emoticon'). I'm not certain of the 'showing feeling' bit.
'turned up book i study' is the wordplay.
'turned up' is a reversal indicator.
'book' becomes 'tome' (a tome is a book).
'study' becomes 'con' (con can mean to study).
'tome' written backwards gives 'emot'.
'emot'+'i'+'con'='EMOTICON'
'for' is the link.
Can you help me to learn more?
(Other definitions for emoticon that I've seen before include "Screen symbol expressing feeling" , "Mince too (anag.)" , "Symbol in email or text message to show joy etc" , "smiley, perhaps?" , "Wordless expression" .)