Love bores little contemptible person (4)
I believe the answer is:
toad
'contemptible person' is the definition.
(I've seen this in another clue)
'love bores little' is the wordplay.
'love' becomes 'o' (love means zero in tennis).
'bores' is an insertion indicator (bore can mean to drill into).
'little' becomes 'tad' (both can mean a small amount).
'o' inserted into 'tad' is 'TOAD'.
(Other definitions for toad that I've seen before include "Dangerous driver" , "Hateful person; animal" , "Wind in Willows hall-owner" , "species of amphibian" , "Froglike animal or repulsive person" .)