Entities that have no in built code nor are written into the code of the uni/multiverse. This means that they are immune to hacking, glitching and deletion though how killable they are by other methods may vary.
“"I... I miss everyone. I just want to go back." – Rho to Alpha Rhosaith is a Time Specter that...Rhosaith
“Is a AU talked Vampire and succubus is a own different timelines like undertale then are maybe...PramaLust
“*NOTE TO ALL READERS* I appreciate that you all enjoy some of my work, but for future reference...The Eternal Worm