Someone who has extensive experience with Ayahuasca:

"When I was in Northern Peru for 7 weeks, and working with Ayahuasca, I met an interesting elderly man. He had spent many years travelling around South America documenting the use of Ayahuasca. From what I recall he was making a documentary. It so happens this man is a seer. He has clairvoyant sight. During a conversation with him he made the comment that he had met very few Ayahuasqueros who did not work with demons or demonic forces."

And also:

In Ancient Hawaiian Huna (as I learnt it, which came from an old and rare lineage as opposed to the Huna that is popular today) these entities are call Malu. Malu translates into “life-taking spirits”. These are spirits or entities that devalue life, depreciate life, take from life. If you go into relationship with a Malu (whether you know it of not—usually not) it will have this effect on you also. It will detract from the flow and expression of Life within you, in your relationship, and in your world. Modern psychology might argue that these Malu are simply aspects of our own psyche. That’s possible, although it fails to adequately explain a few important things. But either way, they are detrimental to our well-being and they have a very real impact on people.

One important aspect of Malu or entities is that once removed from a person’s field, very tangible changes are often experienced by that person. Remove an angry Malu and someone might find they cease having angry issues. Remove a Malu with a propensity for alcohol, and someone with a long-standing alcohol problem is suddenly “cured” of that issue. I could cite hundreds of real-life examples, but that will do for now. I trust it gives you a general picture of what we’re dealing with.

What I have found is that when people get “out-of-it” (to use a term commonly applied to someone who has taken drugs) the luminous body has, to an extent, vacant. That vacancy creates a vacuum of sorts. This “space” was intended to be occupied by sentient consciousness. If your sentient consciousness has checked it, something else is likely to check in. The problem is that this uninvited guest is likely to hang around even after your return.

What is also interesting is that alot of DMT users encounter Alienesque Insectoid entities that more often then not probe or somehow 'experiment' on the person taking DMT.

I have found this from a highly accomplished French Psychic, apologies for the choppy English as it has been translated from French to English using google translate:

The insectoid entities are winged black bottom chart, in relation to the lower vibrations of the spiritual plane. They have a size that can go til 3, 5m for adults. These creatures live in a family of ten individuals. I have no idea of their age because the notion of spending their year is completely unknown.

They are very aware of their role, well organized and very farsighted. Their main food is the spiritual deviations (satanic rituals, initiations bullshit, rituals intended for purposes of power, drugs). They have an ability to detect these phenomena has great distance and they know in advance or it will happen. They go to these events, family, leaving juenes use first.

They have a tube fixed on their 4th chakra allowing them to feed on emotions and a kind of language-very long proboscis, which comes brancer on 7th chakra of the victim and sucks the substance.

You must have done stupid things to be the prey of an insectoid black. Nothing is without reason, they are aware that they make us pay our wanderings and ultimately it is their mission. They are cunning and savvy predators, as their 6th chakra testifies unusually large. Sometimes they are hooks to a human hatch the egg laid in his chest.