Spirits initially not seen — they may be here (5)
I believe the answer is:
hades
'be here' is the definition.
(thesaurus)
I don't understand how the remainder of the clue works.
(Other definitions for hades that I've seen before include "Infernal situation" , "Greek underworld with spirits of the dead" , "Pluto" , "The nether world, hell" , "Inferno" .)