At sixteen years of age, Lily was properly ashamed to admit that she's never once conjured a patronus. She's read all about them, memorized the theory, and even written an essay on them, but for some reason she's never actually conjured one. However, never in her five years and however many months of magical education has she ever considered this to be an inconvenience. But, as Lily knew only too well, there was always a first time for everything.
"James Potter, I am perfectly capable of conjuring a patronus, there is no need-"
"How would you know if you've never actually conjured one?" James cut her off. "For all you know it could be the one spell you can't do." He tugged on her arm, leading her closer to the edge of the forest.
"That's a rubbish reason for dragging me all the way out here…why are we all the way out here?"
"To avoid distractions, Red, now listen up."
"Don't call me-"
"The most important element of the patronus charm," James said loudly over what must have been Lily's hundredth objection to the name, "is the memory you use. You need to think of a happy one."
Lily rolled her eyes. "Obviously."
"Not only happy," he went on, undeterred, "but particularly strong at that. So, although I'm sure our conversations are the light of your murky days, I doubt that even your memories of me are emotionally powerful enough to use."
"Oh, they're emotionally powerful, it's just not the emotion you're looking for…"
"Must you be a spoil sport, Evans? I'm trying to help you here."
She crossed her arms over her chest. "Show me yours."
"You want me to believe you're the 'patronus expert' here, so show me yours."
James smirked. "So…if I show you mine, you'll show me yours, is that it? Oi!" he ducked to avoid Lily's swinging arm, "I was kidding! I'll show you, all right?"
James drew his wand, making a rather large show of concentrating on his memory before saying, "Expecto Patronum." A large stag burst from his wand, galloping at a lazy pace, haphazardly making its way out of sight. James watched it go, entranced, only breaking his concentration when Lily spoke from behind him.
"Was that…a deer?"
James turned, flustered. "It was a stag!"
"So…a boy deer. Much better." Lily was trying not to laugh at James' indignation.
"What have you got against stags?" James ran a hand through his hair irritably.
"Nothing," she shook her head with a smirk. "They're very…graceful," she said pointedly.
"What's that supposed to mean?" By now, James was well on his way to lividity.
"Oh, nothing really, it's just…patronuses are supposed to be powerful. The most powerful forces you can conjure…and yours is a deer."
"It's a stag!" he practically screamed. "It's got," he put his hands to his head, miming the prongs, "antlers!"
Lily raised her eyebrows, seemingly unimpressed.
James removed his hands from his head, shoving them into his pockets instead. "Well, let's see yours then," he all but grumbled.
"Hmm, diverting my attention won't work, you know. I'm not in any position to let you live this down," she said with a smirk, drawing her wand. She closed her eyes, trying to think of a memory to choose. After about a minute, she opened her eyes, raised her wand, and said "Expecto Patronum." A silver mist erupted from her wand, swirling about, and for a moment Lily was afraid it would remain formless, but just as she thought that, it materialized. At the sight of her patronus, she dropped her wand arm, quite unintentionally, and could almost feel James smirk behind her.
"Is that," he said with a hint of suppressed glee to his tone, "a deer?"