That's a quote from wikipedia. To me, it doesn't sound right, but I can't explain why as I haven't read the book, which is written by a reform rabbi (i.e. not a kabbalist), nor do I know why the author of that section of the page wrote it the way they wrote it.
Instead, I'll refer you to Chapter 7 of Tanya, written by an original, authentic kabbalist, which deals with the subject.
To very briefly (and certainly insufficiently) summarise: God created a world, which is left incomplete, and invites us to complete it. The way we do that is by performing good deeds and avoiding bad deeds. Good deeds have a positive effect on the world, and bad deeds have a negative impact.
Kabbalistic metaphor describes three categores - klipa, klipat nogah and kedusha. Klipa, 'husk', is that which hides the Creator, and Kedusha, 'holiness', reveal the Creator. The Klipat nogah is the "touching klipa", the innermost part of the 'husk' that bridges the two.
When a Jew takes something that is neutral, e.g. kosher meat and wine (which get their vitality from the klipat nogah), and consumes them in the way God instructed him to (by following all the laws e.g. saying the correct blessing, and having the correct, pure intentions of only eating it in order to gain energy to further serve his Creator), then:
...it is absorbed within Kedusha... the good that is intermingled in it is extracted and separated from the evil, prevails, and ascends to be absorbed in Kedusha...When one eats and drinks in the above-mentioned manner, then the vitality of the meat and the wine which originated in kelipat nogah is then extracted from the evil and ascends to G‑d like a burnt offering and sacrifice (i.e., the life-force of kelipat nogah that the food and drink contain is absorbed in Sanctity).
If however, he eats that sandwich in an improper way, only to satisfy his cravings, then:
he vitality of the meat and wine that he ingested is thereby degraded and absorbed temporarily in the utter evil of the three unclean kelipot. His (the glutton’s) body becomes a garment and a “vehicle” for these kelipot.
This is very esoteric, of course, but the imagery is clear - the vitality of the neutral items in the world can either ascend or descend. If they ascend, they are given over to revealing God, and if not, they add more obscuration of God in the world, further darkening it, i.e. "vitalizing the klipot".
So, does this create demons, angels etc? Some will say yes (although nobody will say these demons/angels are anything like the stereotypical demons of popular culture), some will say no, it is just a metaphor to add imagery to aid understanding of the above concepts. Some will say that the answers are very deep...
This isn't something an amateur in kabbalah should really be thinking about, as it requires a lot of background and deep understanding. In Tanya, Shaar Hayikhud Ve-ha-emunah, Chapter 1, the Alter Rebbe quotes the Arizal:
"even in the literally inanimate—like stones, dust and water—there is
a soul and spiritual life… which enlivens and creates the inanimate"
-see this article: https://www.chabad.org/library/article_cdo/aid/3432275/jewish/Do-Chabad-Teachings-Say-Anything-About-the-Mind-Body-Problem.htm
"Aristotle famously described G‑d as “thought thinking itself.” But the Maimonidean view, as interpreted by R. Schneur Zalman, is that all reality is divine thought thinking itself."
As you can see, not for amateurs.
EDIT: I recently heard in a shiur that when you lose control to a forbidden desire, that is a demon. This particular sin does indeed "multiply itself", the more one engages in it, the more addictive and demonic it becomes. The idea of "self preservation" comes from the concept of "just one more" combined with "I still haven't had the greatest pleasure, must keep going until I find it and am finally satisfied for good".