Koschei was bored. Bored, bored, bored. He had no work to do, and no Theta there to distract him. He wondered what trouble the other boy had gotten into this time. Probably for bad marks or something like that. Theta never was the most… studious of students. Couldn't keep his mind on anything for more than a few minutes. Although Koschei prided himself in being one of Theta's major distractions. He could be like a love struck puppy at times. And those cute little blushes whenever anything was initiated, just adorable. But he wasn't here right now for any of that, which Koschei felt was rather inconsiderate of him. He wondered over to Theta's belongings, noticing a couple of books lying open. Both of them, unsurprisingly, about Earth. He sighed and shook his head. Why Theta loved that primitive little planet he would never know, although he would never have told Theta that, bless him. He looked down at the first book. It was open to a page explaining about Earth fruits. Apples, bananas, pears, the list went on. He wondered how on Gallifrey his Theta could be interested by some Earth food. He had never seen the attraction. Oh sure, he played along, to please his love, but he was never truly enthused by it. He turned to the next book, which was explaining Earth holidays – Christmas, Easter, Valentine's Day… and then he spotted something that caught his interest. April fool's Day. Now that sounded interesting. A day in which people of the planet Earth would pull pranks on each other, and get away with it. Now there was an idea. Pull a prank on Theta for the sake of April fool's day. Yes. Brilliant. This would help alleviate his boredom no end. Now what prank to pull? It should be something to do with Earth really. He looked back at the first book. He was sure that his Father had some fruit trees in his estates. Oh this was too good an opportunity to pass up, and he had the perfect prank to play on Theta. A sly grin, bordering on evil spread across his face as he ran off to prepare for Theta's return.

A few hours later, once all his preparations were complete, he finally found Theta.
"Oh THERE you are Thete... Come on, I got something to show you!" he said, grabbing his hand and leading him, noting that the other boy's heartbeat quickened the moment touch was initiated. Looking back at Theta's face he saw a cute expression - a mix of adoration and tiredness that almost tempted him to give up on this little prank and just snog him senseless instead. But there would be plenty of time for all that and more later. Right now he was in a bit of a wicked mood. He noticed that the drums were slightly louder than normal, but dismissed it without further thought, deciding instead to think of his prank. And of Theta. His gorgeous Theta.

"Where we going Kos?" Theta asked breathlessly as Kos led him along. Koschei grinned at him.

"It's a surprise!" he responded. "Especially for you!"

"Ooooh!" Theta exclaimed. "What is it?" he asked his lover excitedly. Koschei raised an eyebrow.

"Wouldn't be a surprise if I told you, would it?" Theta thought about this. It was definitely true. He wondered what it could be that Kos had found for him. He was sure that he would like it, whatever it was…

Finally they reached their destination. Koschei gestured to the ground by the tree in is Father's estates which he had chosen, a sign for Theta to sit down. Theta sat, but Koschei remained standing. Now he just had to remember which was the correct one. Theta looked up at him in expectation.

"So why we here Kos? What's this surprise of yours?" Koschei looked down at him fondly, the adorably cute expression on his face. He tried his hardest so keep his smile loving and not smirk and give the whole game away.

"Well I saw those books you were looking at earlier, and I thought it was about time you had a treat… and then I remembered about this…" he stopped, keeping Theta in anticipation. Theta continued to watch him, waiting. "Close your eyes Thete!" he instructed. Theta obeyed without question, screwing his eyes up. Once they were, Koschei reached up to the branches above and plucked the pre-prepared fruit from it, before going over to sit beside his love. He took hold of Theta's hands and pressed the fruit into them. Theta's eyes flickered open and he looked down at the item he had been presented with.

"Is that what I think it is?" he asked, excitement building. Koschei nodded, smiling

"Yup. It's a pear. My Father grew rather partial to them and so had a tree brought from Earth…"

Theta's face lit up as he looked at the fruit in his hand.

"Wow, Kos… you're amazing. I've always wanted to try an Earth fruit. I've heard they're really juicy and sweet…" he blurted, throwing his arms around Koschei. Koschei smirked while Theta couldn't see. Juicy and sweet? Not any more… He was looking forward to seeing Theta's reaction to his little prank…

Theta released him and took another look at the pear held in his hands, before taking a large bite out of it. Koschei watched as his expression of wonder and appreciation quickly turned into one of revulsion as the mix that Koschei had coated the pear in before did its work. Then Theta realised that Koschei was still watching and blushed, afraid to offend him by spitting the bit of fruit out of his mouth, but at the same time unable to stand it being there much longer. In the end he couldn't bear it any longer and spat it out onto the ground spluttering. Koschei looked at Theta, suddenly worried. Had he taken this too far? He couldn't bring himself to admit now that it had all been a prank. All been done on purpose.

"You ok Thete?" he asked tentatively. "What's wrong?" All Theta could do was cough and splutter, and Koschei felt dreadful. He hadn't meant to hurt Theta. Not really. Just shock him a bit. He picked up the discarded pear from the ground and sniffed it. Oh Rassilon, it was stronger than he'd thought. Much stronger. No wonder poor Theta was in the state he was right now. Luckily he had planned ahead. He pulled a small flask of water from his robes and handed it to Theta, who downed it quickly. Slowly he stopped coughing and calmed down. Koschei reached over and pulled him into a tight embrace. "I'm so sorry Theta. Are you alright."

Theta nodded as he fell into the embrace.

"It's not your fault Kos. But those Earth books obviously lied. Or else humans have different taste buds to us, but that was horrible. It burned my mouth, like I was on fire. How can humans bear to eat the things?"

Koschei felt terrible, a deep sense of guilt inside him. He wished he'd never seen those books. Wished he could undo it. But it was too late for that now. But he couldn't quite bring himself to admit what he had done now. That it really was his fault. He'd better think of something to say quickly.

"It is my fault though Thete. I should have tried it first. Made sure it was ok. I just… know how much you like Earth things and thought… well… I'm sorry." He pulled away, so ashamed at himself. Theta obviously noticed his expression, because he put a hand firmly on his arm, and used the other to move Koschei's head round to look into his eyes.

"Don't blame yourself," he said, smiling adoringly once more. "I love you Kos!" he continued, before leaning forward for a passionate kiss. Koschei's guilt quickly slipped away as he wrapped his arms around Theta and pulled him closer. As the kiss broke, Koschei smiled back at Theta.

"And I love you. Always."

The Doctor never did like pears from that day onwards. They thought of that burning feeling always scared him. But never did he suspect that there may have been more to the incident than Koschei let on. He would never have considered that the change from Koschei to the Master had started that early. He chose to remember Koschei as uncorrupted without the insanity that belonged to the Master. His perfect Koschei. He would never be forgotten.