Burning lust in partially vacated part of eastern Europe (9)
I believe the answer is:
pyromania
'burning lust' is the definition.
(lust for burning things)
'partially vacated part of eastern europe' is the wordplay.
'vacated' suggests removing the centre.
'part of eastern europe' becomes 'Romania' (eastern European country).
'partially' with its centre removed is 'py'.
'py'+'romania'='PYROMANIA'
'in' is the link.
(Other definitions for pyromania that I've seen before include "Fire-raising compulsion" , "igniting lots of fires" , "Fire-raising impulse" , "Flaming madness!" , "lighting up for fun?" .)