As Salaam Alaikum!!!!!!!!!!!!!!!
What do you mean by negative spiritual work?
As Salaam Alaikum!!!!!!!!!!!!!!!!!It is more from a magical and intended perspective. Basically it is working with spirits to achieve some form of destructive energy. Mostly applies to the ATRs. Like my god brother has a spirit that if my god brother writes a name of a person and places it on the spirit's house, that person will die in 21 days.
Negative work like that. Those of us who are practitioners call any interaction we have with our spirits towards a certain goal "work" or "travay" or "trabajo".