This story was written for two reasons. One: Upa is fucking adorable. Two: there isn't enough Goku x Upa. Enjoy!
Goku and Upa were walking through the forest, which was quite tranquil with the exception of twigs snapping and leaves crunching when they were stepped on. The two boys had been out this far into the wilderness before, but not in this particular part.
"So Upa, where is this river you're talking about?" Goku asked, "I'm starving!" Upa giggled as he handed his friend a small piece of venison. "It's just up here, I promise," he said, pointing forward through a mess of foliage and branches. "Why can't I use my Nimbus?" Goku questioned. He didn't like to walk at all. He took his Nimbus when possible because he didn't want his feet to hurt. "Well, I thought it would be nice for us to take a walk instead," Upa explained, pushing some bushes out of the way. They had just exited the forest and arrived at the river. "The sound of water is so relaxing, don't you think so Goku?" he asked. "Yeah, it is. It's an interesting sound," Goku replied as he took off his pants. "Goku, what are you doing?!" Upa gasped, "Why are you taking your clothes off?!" Goku cocked his head to the side. "What's the big deal? I always fish like this!" he said, removing his shirt and dipping his tail in the water. "But I don't have a tail," Upa told him, baiting his hook. "Oh, that reminds me," Goku said as he walked over to his friend. He patted Upa's crotch, noticing that he was hard. "You're a boy, all right. But why's it all pointy like that?" he asked.
"Well Goku, I like you," Upa said as his cheeks turned bright red. "I like you too. You're really nice," Goku replied with a smile. "No, Goku. I mean I l-love... you," he confessed. He covered his erection when he noticed that the small bulge in his buckskin pants was growing. "Wow. Well, that explains a lot," Goku told him, his face also growing red. "Well, I suppose you think I'm sort of weird now. I'm sorry Goku, I know you don't love me. I still love you though, and I'm sorry I can't change that. I just-"
Upa was cut off when Goku puckered up and gave him a kiss. It was just a small kiss with their mouths closed. Goku looked down and noticed that he had an erection as well. Upa pulled him closer for a hug. It took a while for him to notice that the hug was causing Goku's penis to rub against the bulge his buckskin pants. Goku moaned with pleasure when he felt Upa's member against his own, even if there was fabric between them. "Wow, Upa. That felt really good," Goku said. "I can make it feel even better," Upa replied as he removed his clothes. Upa had never had an experience like this before, but he was excited to. Goku and Upa rubbed their penises together slowly. Upa used his free hand to trace up and down Goku's chest. He liked that Goku was a bit chubby, but not too chubby. He thought it was adorable. Upa held both of their penises in his hand, slowly moving the hand back and forth. He and Goku moaned together. They kissed again. Both of them opened their mouth, allowing the other to use his tongue. Upa explored Goku's mouth, being especially playful with his tongue. Goku used one hand to gently grope Upa's ass. He was surprised at how good Upa was at kissing. They parted and Upa knelt down and began to suck Goku's hard member. Goku's head flew back and his knees were almost certainly about to collapse. Wow, that felt good! It was all he could do to remain standing. "Wow Upa, I've never felt anything this good!" Goku moaned. He felt as if someone had grabbed his tail. He couldn't move if he wanted to. He was quivering profusely. Not quivering like he was nervous, he was quite literally shaking like a tree in a windstorm. Goku felt his penis throb for a moment. After it stopped, he felt even better than before. "What happened?" he asked, looking down at Upa. "That's what happens when you make it feel really good for a long time," Upa said, swallowing Goku's load. "But why didn't you do it too?" Goku asked, still trying to stay upright. "Well, you've gotta let me do something else," Upa explained, "Just lie down on your back." Goku did as Upa said and lay down. Upa got in between Goku's legs. Goku put his legs up, having his knees bend over Upa's shoulders. "Are you ready Goku?" Upa asked with a smile, "I want to make sure so I don't hurt you." Goku nodded. He returned the nod and put the first inch or so of his penis in. A lustful moan escaped Goku's mouth as he felt it enter him. Upa went in a bit further, being especially careful not to hurt Goku. "Does that feel good to you?" he asked. "Yeah," Goku said as his tongue lolled out of his mouth. Upa finally made it in as far as he could. "Okay Goku, I'm going to keep doing this a bit faster," he said, pulling most of his penis out of Goku. He thrust back in quickly but carefully. Although it took a few tries, Upa finally found Goku's sweet spot. "Ngh, aaaah! Upa, that felt amazing!" he gasped. Upa kept going back in and out in the same spot, causing Goku to drool from the pleasure. Finally, it happened. Upa gave as much warning as he could. "G-Goku, I'm going to! I can feel it!" was all he could manage before he came inside of Goku. Upa slowly pulled out. "Was that good for you too?" Upa asked. "Amazing," he replied as he wiped the drool from his cheek. They both got dressed and looked up at the sky. "Oh no, the sun is setting! We forgot to catch any fish!" Upa panicked. Goku walked over to the river and punched the water. Dozens of fish came flying out of the water, right into Goku's hands. "Problem solved," he said, smiling at Upa. "You just keep amazing me," Upa said, returning the smile. Goku called for his flying Nimbus. Upa climbed on with him and they began their flight back.
Thanks for reading! A review is always appreciated! Also, someone PLEASE write some Goku x Upa! There's never enough!