Author's Note: This is hopefully not only the first Steven Universe fanfic I've written, but also the first that anyone's written. Yeah, it's a bit early since the show hasn't aired yet, but hey. The early bird always gets the worm.
In the dead of the night, Steven sat on the top of the Gems' headquarters. As was par for the course, he was moping over the fact that he had yet to figure out how to activate his gem powers. Suddenly, he heard someone approaching him from behind. He turned around and saw it was only Amethyst. It was always nice to see the violet-hued Crystal Gem in all her beauty.
"Steven, it's, like, midnight." she said out of concern. "What are you doing up here?"
"Nothing, I guess." the boy just grumbled.
"Nothing, huh?" Amethyst asked. "Well, Garnet and Pearl want me to take you back inside. You want to come in?"
"Not right now." Steven replied.
"Okay." was all she could say before she started walking back through the way she came.
It was then that Steven now felt like saying something, so he ran towards the Crystal Gem and blocked her path.
"What are you doing?" she asked, now getting irritated at the fact that he was playing roadblock. "You better have a good reason for this."
The prepubescent boy sighed. He replied with, "Yes. Yes I do. Amethyst, there's something I've been meaning to tell you for the longest time since... ever. I...I..."
One of Amethyst's eyebrows perked up. "Are you trying to tell me what I think you're trying to tell me?" she asked out of curiosity.
"Yes! I really like you, Amethyst. I really do!" Steven blurted out. "There."
They just stood there in silence for a minute.
"That's all?" the violet Crystal Gem laughed lightly. "I expected something a bit cornier, but that's good enough for me. I don't mind that kind of stuff anyway... Y'know, come to think of it, I was going to tell you the same thing."
"You really like me, too?" the boy asked.
"How'd you know?" she asked.
"It must be Gem intuiton, I guess."
"Ah. I forgot to mention we had that. You want me to kiss you?"
"Oh boy, would I!"
Amethyst and Steven embraced themselves while their lips touched each other, lock and key. It was at that moment that their gems started glowing. Steven broke away from the kiss while still holding on to his girl, and he seemed to be panicking.
"What's going on?" he started asking. "Why are our gems glowing? And why does it feel like something just sprang inside my pants?"
"I think we aroused each other so much that it's activating our gems." she explained. "And it feels like something sprang in your pants because it did spring in your pants. In other words, you're excited."
She kissed him again and they started to float upward into the air. Steven still hung on to her and he could feel his testosterone levels spiking. He pushed his tongue into her mouth and started to wipe it over the external surface of her teeth, which she couldn't feel since she was too invested in moaning and making guttural sounds.
"Oh yes, Steven!" Amethyst finally screamed. "This is amazing! I've never felt this high in my life!"
"What happens if we go, uh, 'all the way?'" he asked.
There was no answer. He probably wouldn't have heard her anyway, for now there was a loud screeching sound followed by a blinding white light coming from her gem. When that passed, Steven looked around to find that they had managed to set a huge chunk of a forest below them on fire, and there were several people also below them screaming for their lives.
"Wow!" Steven exclaimed. "Did you see that, Amethyst? We started a fire!"
Again, there wasn't an answer. Amethyst just smiled softly at him and her eyes looked to have been drained of all energy whatsoever.
"Steven..." she spoke hoarsely.
"Y-yes?" he asked quietly.
"H-how do you know?"
"As you said, it must be Gem intuiton."
And thus began a new life for them both.