(AN: So this is based off of a tumblr post I saw, so the idea is credited to the person who thought of that. I DO NOT OWN HP OR ANYTHING IN IT! THOSE ALL BELONG TO JKR!)

James Potter had had his fair share of surprises throughout his time at Hogwarts. One of his best friends was a werewolf for crying out loud! Yet, for the rest of his life, one surprise would stick with him forevermore.

They were all in Defense Against the Dark Arts in their sixth year. There was only about a month left of school and they had finally reached the part that many in their class had been dying to learn: Patronuses. So, after a week of theory, wand movements, and practicing enunciation, they were finally attempting to cast the advanced charm.

The classroom was filled with sixth years waving their wands in front of them and casting. Shouts of "Expecto Patronum!" echoed against the stone walls and out the open window. Silver mist soon became so thick that everyone's vision was obscured. As nearly every student concentrated until their faces turned blue.

However, in the very back corner of the classroom, hidden by the misty vapor, four boys sat, watching the others. Two boys, both with black hair, one with glasses, were watching smugly, a boy with sandy brown hair's eyes kept flickering to his wand, as if he wanted to join in, and the little mousy boy beside them… well, he just sort of looked like he was in the best place in the world. The boy with the glasses turned to the sandy-haired one. "I still don't see why you want to join in, Remus. We mastered this forever ago."

His friend just rolled his eyes. "It wouldn't hurt to practice, James," Remus replied. He looked exasperated, as if he had argued this several times already. However, despite his insistence to hone their skills, he stayed put by the others.

The other dark haired boy nudged James. "Hey," he said. "Looks like you've got Evans beat on this one."

"Shut up, Sirius," James snapped, though he couldn't stop the the blush creeping up his cheeks. His gaze darted over to where a pretty redhead was stamping her foot in frustration before waving her wand once more. He fought back a smile at the exasperated look on her face. She was just so beautiful…

"Hello? Earth to Prongs!" James blinked as Sirius waved his hand in front of his face. He elbowed his friend in the ribs before turning away. Peter, their other friend, laughed while Remus merely rolled his eyes.

"Alright class!" their professor called, shouting to be heard over the noise in the room. "I would like you all to return to your seats, and I will call you up one at a time to present your progress. Starting with Mr. Black."

Smirking, Sirius strutted straight to the front of the room. Taking a moment to look around dramatically, he raised his wand and shouted, "Expecto Patronum!" Several people made sounds of amazement as a large dog burst from the end of Sirius's wand, running around the room once before fading away. The professor grinned and applauded slightly.

"Well done, Mr. Black!" he said. "Very well done!"

One at a time, students were called up. It was a rather large NEWT level class in Defense this year, so it took a fair amount of time. Finally, to James's delight, Lily Evans was called up.

The red-haired girl was biting her lip nervously, which James understood. She was top of her class in everything, so failing at her Patronus would be humiliating for her. Others had been unable to cast one yet, and no one had managed a corporeal like Sirius, but Lily would expect nothing but perfection from herself.

Shaking slightly, she took a deep breath, closed her eyes, and shouted the spell, face screwed up in concentration. For the second time that day, a gorgeous animal was cast. But it was… it was…

"A beautiful doe, Ms. Evans!" the professor said excitedly. Lily grinned in joy as her patronus faded away into nothingness. The class once again gave applause.

However, four boys did not even lift their hands. James, Sirius, Remus, and Peter all exchanged open-mouthed glances. Lily glared at James as she passed him. "What?" she asked. "Did you think I wouldn't be able to do it?"

This was not, of course, the case. The marauders did not at all doubt her ability, but the form her Patronus took…

By the end of the class, only those two had managed full-body Patronuses. Peter was not quite as skilled as his friends, and Remus and James had both asked to perform theirs after everyone left.

Lily Evans was suspicious. She didn't know what was said, but both Remus and James had gone up, whispered something to the professor, and sat back down without casting. What had excused them from performing like everyone else? Fuming, she stomped out as soon as the class ended. Of course, in her hurry to get out, she had managed to forget her Transfiguration textbook, which just had to be her next class.

She raced back to the room, praying she wouldn't end up late. However, right outside the door, she heard voices. Pausing, she peered through the slight opening. James Potter and the professor were both inside.

"Yes, Mr. Potter, now I understand why Mr. Lupin didn't wish to perform the charm in front of his classmates. But why you?"

To Lily's shock, James shuffled nervously. "Well, professor, I was trying to avoid embarrassment. Not for me, necessarily, but for someone else."

The professor nodded, even though he was still slightly confused. "Well, proceed then."

James pulled out his wand and cleared his throat. He hesitated for only a second before conjuring up a happy thought. It just took a single flashback to the previous class, the memory of a silver doe prancing around the room, before he was ready. "Expecto Patronum!"

The large stag flew from his wand, shining blindingly bright. He held it there for a moment, letting it strut around a bit, before whisking it away.

The professor's eyes were the size of saucers. "Mr. Potter! That was the strongest Patronus I have ever had the pleasure of seeing! What thought could have induced such a thing?"

James just shrugged with a small smile. Meanwhile, Lily was sitting with her back against the wall, mouth open. Potter's Patronus was a stag? The counterpart to her doe? And not only that, but he had waited until after everyone left to cast it, so as not to embarrass her?

Just like that, she was questioning everything she had ever known about James Potter.

(Not my best work, but I figured it was a cute idea so... yeah, thanks for reading!)