It was at that moment when Gohan was absorbed that it seemed all hope have come to an end. As Majin Buu power dramatically increased, Buu did not anticipate of one fact. Gohan has proved to be too strong both physical and mental for Buu to just control over his power, and this greatly caused the absorption to backfire against Buu himself.
As Gohan was inside, he still has enough consciousness to battle against Buu mentally. In the end, Gohan was pretty much stronger or at least mentally which gave him enough power to kill Buu inside his mind and that made Gohan enable to have control over Majin Buu's body. He used this opportunity and released all those who have been absorbed including Good Buu out of Buu's body.
Unfortunately for Gohan though, he never has an opportunity to release himself. During the releasing processes and burst everyone out of the body, Gohan accidentally ripped and opened the dimension wall and sent him within Buu's body across the Space-Time Continuum.
Gohan trapped in both Buu's body and Event Horizon displaced outside of Time and Space, where he remained for over 100,000 years. Of course he went insane at first but Gohan eventually learned how to deal with it and regained his sanity back. Since he could not get out of Buu's body by his own for some reason, he learned how to use Buu's power during his time there.
Gohan now has ability to control his own existence and could rewrite himself to be anything he wanted. This was mostly an upgrade version of Buu's Body Manipulation. He used this ability to transform Buu's body to get his appearance back. Now he looked around early 20s without pink skin since his Body Manipulation was at higher level, changing skin color was not that hard. He also learned some techniques Buu used during his time from Buu's Memory thank to Buu's Instant Learning.
Now, after spent over 100,000 years in Event Horizon, Gohan soon had complete understanding of the space-time continuum which enabled him to teleport to any location, both in time and space, slow down or speed up time as he pleased. Though, crossing Time and Dimension could not do constantly for the sake of keeping the timestream on a stable course.
With new powers in his disposal, what kind of change this Majin would bring to the Omniverse...
END
TO BE CONTINUE IN SEQUEL
