Last of several tattoos for couple (4)
I believe the answer is:
link
'for couple' is the definition.
(couple can mean to link or join)
'last of several tattoos' is the wordplay.
'last of' indicates one should take the final letters.
'tattoos' becomes 'ink' (I've seen this in another clue).
The last letter of 'several' is 'l'.
'l'+'ink'='LINK'
(Other definitions for link that I've seen before include "Connect" , "Physically join" , "Make a connection" , "One ring or loop of a chain" , "Relationship; intertwine" .)