the first thing I thought of when I saw this
To the person asking about black shadows and white shadows. Black shadows are typically those spirits who have not passed on yet and are stuck in between realms. They are also known for being mischievous and not typically good spirits per say. Not all are bad or demons because not every single one is but if there are specific ones lurking and following you then be mindful to not pay so much attention to them. They tend to latch on. White spirits are entities that are able pass through realms.