After settling things with Lazuli, Son Goku returned to West City with everyone.
As soon as he got home, Son Goku called Chi-Chi and Bulma over and came clean about Lazuli.
Both women were furious. Seeing their reaction, Son Goku used his Godly Power to conjure a washboard out of thin air and knelt on it with a sincere expression.
"Lazuli and I fell in love at first sight," he told them. "I love her, and I hope you'll give us your blessing."
Chi-Chi flew into a rage. "You call that love? You just want her body, you shameless bastard!"
Bulma chimed in, "Aren't the two of us enough for you? You're still out there chasing other women?"
Son Goku grinned. "Neither of you can handle me. You're always the first to surrender."
Both women snapped, "Fine, Goku, just you wait! Tonight, we'll go three hundred rounds and see who surrenders first!"
"So do you agree to let me be with Lazuli?" Son Goku asked.
"Beat us tonight, then we'll talk," Bulma said.
Son Goku was delighted. "All right! Tonight, we'll settle this!"
Chi-Chi and Bulma gave indignant little huffs, then turned and left.
Only after they had gone did Son Goku get up and put away the washboard. As he headed outside, he saw Son Goshin and Son Gohin standing by the door, staring at him.
He walked up to them. "What are you two little brats looking at?"
"Father, did Mother agree to let you be with Aunt Lazuli?" Son Goshin asked.
"Children shouldn't pry into adult affairs," Son Goku said. "If you have time to spare, go look after your little brother and sister."
"Oh, understood, Father," Son Goshin said.
He turned and called Son Gohin over, then went with him to check on their little brother, Son Kesi, and their little sister, Bulla.
After the two boys left, Son Goku fetched Trunks, and they headed to Kami's Lookout.
After greeting Mr. Popo and Dende, they entered the Hyperbolic Time Chamber.
Son Goku began teaching Trunks how to transform into Super Saiyan 4.
Son Goku created an artificial moon with his bare hands, then told Trunks to look at it.
Before long, Trunks transformed into a great ape over ten meters tall. Son Goku tested him and discovered that he had retained his awareness. Just what you'd expect from the prince's bloodline, he marveled inwardly.
He then told Trunks to transform into a golden great ape, which Trunks did effortlessly.
Next, Son Goku instructed Trunks to compress the energy inside his body and begin transforming into Super Saiyan 4.
Trunks roared continuously in his golden great ape form as his body gradually shrank.
Moments later, a muscular Trunks stood before Son Goku. Red fur covered his upper body, leaving only his chest bare, while leather pants covered his lower half. His hair was black, his eyes were rimmed in red, and his pupils were emerald green.
Son Goku conjured a mirror and placed it in front of Trunks. Trunks took one look, and the mirror exploded.
Son Goku laughed. "Trunks, you're so handsome you blew up the mirror!"
"Uncle Goku, I did it!" Trunks exclaimed in delight.
Son Goku nodded. "You succeeded on your first try because your physical strength and power level were already up to the required standard."
"Uncle Goku, do you mean both physical strength and power level have to reach a certain standard before you can become a Super Saiyan 4?" Trunks asked.
"Exactly," Son Goku said. "If your power level is too low, you won't have enough energy to become a golden great ape. If your body isn't strong enough, you won't be able to compress that energy and shrink your body to become a Super Saiyan 4. You need both."
"I see. I understand now," Trunks said.
Son Goku nodded. "Stay here and keep getting used to Super Saiyan 4, Trunks. I'll head out first."
"Understood, Uncle Goku. Go ahead," Trunks said.
Son Goku nodded, then punched through the Hyperbolic Time Chamber's dimensional barrier and stepped out.
"Goku, didn't you only just go in?" Mr. Popo asked. "Why are you out already?"
"I taught Trunks the training method, so there was nothing else for me to do," Son Goku said. "That's why I came out. Trunks is still training inside."
"I see," Mr. Popo said.
Son Goku said goodbye to Dende as well, then used Instant Transmission to return home.
That night, Son Goku entered the bedroom and saw Chi-Chi and Bulma, both carefully dressed up. Without another word, he pounced.
One dragon romped with two phoenixes. With his limitless stamina, Son Goku soon had both women admitting defeat.
At noon, Son Goku woke to his stomach growling. He moved the two women aside, left the bedroom, and went to the kitchen to order the robot to make him some food.
After wolfing down his lunch, Son Goku immediately set out to find Lazuli.
Just as he was about to get up and go find her, he sensed an immensely powerful energy several thousand kilometers away, battling three other energies.
Everyone training in the Gravity Room sensed it too and rushed outside. Seeing Son Goku, Piccolo asked, "Goku, who's fighting?"
"It should be Lazuli and the other two fighting some stranger," Son Goku said. "Come on, let's take a look."
"All right, Goku," Piccolo said.
Everyone formed a circle around Son Goku. Standing in the middle, he used Instant Transmission, and they soon arrived at the battlefield.
They saw Android 16, Lapis, and Lazuli being driven back relentlessly by a green, spotted monster.
Son Goku called out to the spotted monster, "Cell, long time no see! Stop fighting for a moment."
At his words, Cell actually stopped.
Seeing this, Android 16 and the others stopped as well, then retreated to Son Goku's side.
"Son Goku, how do you know who I am?" Cell asked.
"I saw you in Trunks's timeline," Son Goku said. "Of course I know you exist."
"How come I've never seen you?" Cell asked, puzzled.
"Of course you haven't," Son Goku said. "You aren't the Cell from the world of the Trunks I know. Trunks killed that world's Cell long ago."
"Son Goku, what are you talking about? That's complete nonsense," Cell said.
"Let me put it this way," Son Goku said. "Call this world of mine the main world, and call the future world I visited parallel world one. The world you came from would be parallel world two. Does that make sense?"
Cell nodded. "So you're saying I came to the wrong timeline?"
"Exactly, Cell," Son Goku said. "This world isn't your world's past. It's the past of parallel world one."
Realization dawned on Cell. "I see. Still, that doesn't matter, as long as Android 18 is here."
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