The Z Sword breaks due to a training-related accident with the strongest metal in the universe, Katchin. Old Kai comes out but becomes hostile towards Goku for playfully attacking him with an energy blast.
Old Kai is capable of unlocking Gohan's inner latent potential called the "Mystic Powers," but he refuses to. Goku tries to bribe him with an offer to kiss an Earthling woman (his first choice was Videl, but Gohan refused because Videl is his girlfriend, and Goku settles on Bulma even though Gohan is afraid of her reaction).
Old pervert Kai agrees and begins training Gohan.
Because Mr. Satan claimed to have destroyed Super Perfect Cell several years ago and now that the Earth is in danger again, the people turn to him for help. Arriving at Majin Buu's house,
Mr. Satan befriends the pink monster and even convinces him to give up killing. Majin Buu adopts a puppy he decides to call Bee, and things seem to be going well. Then, the two mad men, Van Zant and Smitty, arrive and shoot Bee.
After Van Zant and Smitty shoot Bee and later Mr. Satan, Fat Buu becomes more enraged than he has ever been after healing Bee and Mr. Satan. In order to keep control,
He uses fission to expel all the inner evil from his body.
The evil leaves Buu in the form of a giant cloud, taking most of his power with it and giving birth to a tall, thin, and gray version of himself called Evil Buu.
Evil Buu kills Van Zant with a massive energy blast and then confronts Good Buu.
Good Buu fights valiantly but proves to be no match for Evil Buu, as Buu had expelled the bulk of his power along with his evil. Desperate, Good Buu fires the
Transfiguration Beam at Evil Buu, but Evil Buu simply deflects it back at him.
Good Buu is turned into chocolate and quickly eaten by Evil Buu, who then transforms into the super-intelligent and incredibly powerful Super Buu. Terrified, Smitty fires at Buu with a machine gun, but to no avail due to Buu's regeneration.
Buu liquifies his body and flies down Smitty's throat, causing him to swell up and explode. Buu regenerates and then sees Mr. Satan and Bee. He rushes over to attack them but suddenly stops.
After a few moments, he utters Mr. Satan's name and then flies away. Through this, Mr. Satan realizes that the good Buu is still in Super Buu somewhere.
Now able to sense Ki, Buu flies to Kami's Lookout, where the Dragon Team and their friends are waiting for Trunks and Goten to perfect the Fusion Dance; however, at the moment, the two are asleep.
Buu appeared and demanded to see the strong fighter that Goku promised him, but he is a day early.
Desperate, Piccolo begs him to wait a bit longer and tells him to spend the time killing some humans, knowing that they can use the Dragon Balls to bring them back.
Eero, standing far away, frowned, looked at Piccolo, and shook his head. "These guys really consider humans as playthings, killing and then reviving, similar to breaking and repairing toys."
After a quick walk around the lookout, just as Buu was about to unleash the Human Extinction Attack,
"It seems I have no choice left," a voice sounded. Piccolo and others startled, looked in the direction of the sound, including Buu, turned, and glanced at Eero, revealing his body.
"When did you? Why are you here? No mortal human is allowed on the Kami Lookout tower," Piccolo's brow furrowed.
Eero turned and glanced at him expressionlessly, didn't reply, glanced at Buu, and spoke calmly, "How about I fight you?"
"Little Eero," Chi-Chi spoke, looking at Eero. Bulma and others were also surprised. King Kai and Supreme Kai were surprised, looking at Eero suspiciously and thoughtfully. 'What does this guy want to do?'
"Very well, I will start killing all those maggots; you are the first," Buu spoke with an evil expression on his face.
Domain Dual Layers x1024
Instantly, 2048 kilometers were shrouded in Eero's domain. Eero glared at Buu and glanced at others frozen around.
"What have you done? Why has my movement slowed down so much?" Buu asked with a frown.
"Whaaaat!!!" King Kai and Supreme Kai on other planets were shocked and stood up from their seats horrified. "Time ability!!! How can this human have time ability?" Their chins almost dislocated in shock.
"What happened?" Goku and Gohan asked curiously, looking at Supreme Kai's shocked expression in front of them.
Supreme Kai spoke, explaining the situation happening on Earth and also about Eero and the time ability, shocking both of them.
On the other side, Eero glared at Buu's body, which looked like it was not affected by the domain and the surprised expressions on his face. 'It seems my time domain also works similarly to the gravity field. A 2-fold domain reduces the speed by 50%, 4-fold reduces it by 25%, 8-fold reduces it to 12.5%, 128-fold reduces it to 0.8%, and 1024-fold reduces it to almost 0.01%. Even the speed of light in my domain is reduced to 300 km/s, which is almost a hundred times slower than my own 25000 km/s speed because of Dual Domain. So my only weapon to destroy this guy is mass inertia and kinetic energy.'
[25000 meters/second agility × 1024-fold domain = 2.5 million meters/second or 25000 km/s]
Eero threw, and the next second appeared in front of Buu, punched his face using full force, looking at his constantly diluting face and changing expression, and spoke calmly, "My domain is enough to reduce your speed, which is around 6000 km/s to 11 km/s. You are like a toddler in front of my 25000 km/s speed. Anyway, a guy like you can't understand these calculations."
"You bastard," Buu flew back; his shredded face returned to normal, halted in the air, and attacked Eero with energy blasts shooting through both his hands.
Eero raised his hand, pointed at the incoming Ki blast attacks, and reminded, "Don't struggle. I know about your strength and also know about your weakness."
Arc-like bullets discharged all those incoming Ki blast attacks; his few Ki arcs pierced through Buu's body Ki layer and embedded inside his body before he could react.
Thud! Shrub!
The arc-shaped bullets expanded in his body, eating away the parts of Evil Majin Buu's body.
"Also, my energy, physicality, and any movement are 2000 times faster and stronger than yours. It seems you are nothing special. I underestimated my ability and overestimated your capabilities."
...