Soft-hearted German negative over cutting rent (7)
I believe the answer is:
lenient
'soft-hearted' is the definition.
(I've seen this before)
'german negative over cutting rent' is the wordplay.
'german negative' becomes 'nein' (I've seen this in another clue).
'over' is a reversal indicator.
'cutting' is an insertion indicator (some letters cut their way into a word).
'rent' becomes 'let' (I've seen this in another clue).
'nein' written backwards gives 'nien'.
'nien' inserted inside 'let' is 'LENIENT'.
(Other definitions for lenient that I've seen before include "Tolerant, rather than strict" , "Light" , "Easy, soft" , "Clement" , "Forgiving, gentle" .)