2000 guards like going round Black Sea spa seeking morbid type of pleasure (9)
I believe the answer is:
masochism
'seeking morbid type of pleasure' is the definition.
(masochism is a type of sexual pleasure)
'2000 guards like going round black sea spa' is the wordplay.
'2000' becomes 'mm'.
'guards' indicates putting letters inside.
'like' becomes 'as'.
'going round' indicates putting letters inside.
'black sea spa' becomes 'sochi' (Russian spa town on the Black Sea).
'as' placed around 'sochi' is 'asochis'.
'mm' enclosing 'asochis' is 'MASOCHISM'.
(Other definitions for masochism that I've seen before include "sex-based pleasure" , "Tendency to enjoy one's own suffering" , "Morbid gratification in suffering pain" .)