Shower of affection coming out of Barkis — seriously! (6)
I believe the answer is:
kisser
'shower of affection' is the definition.
(something which shows affection)
'coming out of barkis seriously' is the wordplay.
'coming out of' indicates a hidden word.
'KISSER' is hidden within 'barkis seriously'.
(Other definitions for kisser that I've seen before include "Mouth (slang)" , "Amorous type" , "Skiers (anag.)" , "Slangy face of osculatory origin" , "Casanova" .)