For as much work Dr. Arinsu has put into her back-up plan, her main plan revolves around the essence of Majin Buu she obtained prior to the beginning of Dragon Ball DAIMA. Aside from Glorio, Arinsu has Marba, the ancient sorceress truly responsible for creating Majin Buu, in her employ. With her own scientific genius and Marba’s mystical prowess, Arinsu is using her Buu piece to create a demon even more powerful than him.
While Glorio’s subservience to Arinsu is absolute, as is made clear by him referring to her in Episode 8 as “Arinsu-sama,” she needed to persuade Marba to work with her. To do this, she promised to grant Marba a position of high status after she becomes the Supreme Queen of the Demon Realm. Not only is Marba useful for creating new Majins, but for psychically connecting Arinsu to them. Because Arinsu has mixed her spit with Majin Buu’s essence, she’ll be able to telepathically speak with Marba’s new creations, just as Bibidi and Babidi were able to speak directly into Buu’s mind.
Gomah is an exceptionally powerful sorcerer, which is how he became the right-hand of Dabura in the first place. However, he isn’t nearly as strong as Majin Buu. When Gomah launched his attack on the Z-Warriors, he needed to use Earth’s Dragon Balls, not the Demon Realm’s, as he isn’t strong enough to defeat any of the Tamagami. By contrast, a de-aged Super Saiyan Goku has already defeated Tamagami 3 with minimal effort. With a warrior, or potentially multiple warriors, more powerful than Buu under her command, Arinsu will have more than enough power to overthrow Gomah, eliminate Degesu, and dispatch any Z-Warriors who attempt to stand against her.
While Arinsu’s full motivations are yet to be revealed, everything fans have learned about suggests she intends to rule as a cruel queen. According to Shin, she stayed in the Demon Realm when most of the other Glinds abandoned it because of her grand ambitions, and her desire for thrills. More Recently, she created the obedience collars that Dabura placed on every citizen of the Third Demon World, and which the Gendarmerie continue to use to torment the population.