Kiss partner and start to drink revealing a betrayal
I believe the answer is:
telltale
'a betrayal' is the definition.
(thesaurus)
'kiss partner and start to drink' is the wordplay.
'kiss partner' becomes 'tell' (I am not sure about this - if you are sure you should believe this answer much more).
'and' means one lot of letters go next to another.
'start' indicates taking the first letters.
'drink' becomes 'ale' (ale is a kind of drink).
The initial letter of 'to' is 't'.
'tell'+'t'+'ale'='TELLTALE'
'revealing' is the link.
Can you help me to learn more?
(Other definitions for telltale that I've seen before include "Monitoring device - gossip" , "Blabbing person" , "Blabber of secrets" , "One spreads other people's secrets" , "Revealer of secrets" .)