Oliver decided that he should change Gabriel even more, he always had a kink/fetish for monster-girls and horny, incest loving older sisters, so with that being said he might as well turn Gabriel to match.
Oliver began using the Chronivac, the first thing he did was freeze Gabriel so he couldn't change more until Oliver set the new changes up, secondly he made it so if his parents and little sister return they would be teleported and not move, in their rooms.
Now Oliver got done to changing Gabriel.
Oliver made it so Gabriel would keep his memories of being a guy, but gain new memories of what Oliver is changing him into.
Oliver turned Gabriel into a succubus but instead of having legs his lower half would be a dragon tail (dragon lamia). Oliver made Gabriel 7'3" tall from the waist up and gave him 10 G cup breasts (5 pairs), from the hip down Gabriel's serpent body would be 20'1" long. Nestled in Gabriel's succubus hips will be a pussy, then on Gabriel's serpent body would be 2 more cunts in a row below and they would be surrounded by 4 E cup breasts each. Oliver then gave Gabriel 7 pairs of arms, he made Gabriel's demonic skin to be a scarlet red, while the scales on Gabriel's serpent body would be black with some red. Gabriel would get a nice bubbly ass and ass length black hair, he would also get a pair of long black horns that curled around his new elf ears. Since Gabriel was going to be a succubus serpent Oliver didn't need to alter much after since succubi bodies are made for sex and fulfilling peoples kinks and fetishes.
The only thing left for Oliver to change was how Gabriel would be as his older sister, so he made it that Gabriel would be the motherly older sister who loved to take care of her family's sexual needs and was your stereotypical extrovert girl. Now all he needed to do was give his new sister a name, but he wasn't any good with coming up one for her so he decided to leave her name as it was, Oliver hit enter and unfroze Gabriel to watch him change.
Gabriel couldn't stop jacking off, it was feeling better and better as he did even though he knew it was changing him. He watched in the mirror and felt as his torso grew taller and curvier by the second, his hair lengthened, and his hips widened. Gabriel felt a pressure grew behind his nipples and saw his chest rise blocking his view down his chest, his shirt ripped revealing a pair of breasts with large areoles and nipples. Gabriel picked up the pace with his masturbation and using his free hand began to fondle his new large breasts. As Gabriel masturbated faster and harder the changes came faster. Gabriel felt as the sensitivity of his body rise, as his dick shrank into a cock hungry succubus pussy, as he became a she, she lost herself to the pleasure of her changing body, and her changes ended with the greatest orgasm she has ever felt in her life, Gabriel blacked out from the orgasm.
Oliver watched masturbated to Gabriel changes and came when Gabriel reached climax. Oliver then quickly went on using the Chronivac to change his house to accommodate his new sister, he gave himself memories of her, and then teleported her to her room. He then heard a beep from the Chronivac and saw his family had returned. Oliver smiled to himself, now it was time to change the rest of his family.