Disclaimer: I do not own Fairy Tail
...10 years later...
"There you are! Where have you been Zeref? I was looking all over for you!"
"Go away, Mavis."
"Wh - What? Why?"
"It doesn't matter, just leave me alone."
A deafening silence ensued.
"No."
"What?" the one named Zeref whirled around to stare at the girl.
"Something's bothering you," Mavis said simply, "What's wrong? You can tell me."
"I - I," he ran his slim hands through his dark hair, trying in vain to find words, "Look," he finally said.
Mavis looked, she took in his disheveled appearance: the dark circles under his coal-black eyes, his worried frown, and the way he gripped his slender hands as if he wished to severe it from his body.
Finally, with a slight gasp, she noticed the deadened landscape; wilted flowers dotted the brown grass and there were no animals in sight.
"Y - Your magic finally manifested," she said hesitantly.
"That's right," Zeref intoned emotionlessly.
"And your aptitude is - "
"Death Magic."
"Death Magic," she mused, "magic that cannot be controlled as long as the mage remembers the value of life. Thought to be a Lost Magic and often referred to as a curse…"
Zeref had heard enough, "I'll be going now," he said quietly. But his departure was abruptly stopped by a pair of arms that flung around his torso, locking him in place.
"You're my best friend," she said into his shoulder, "I don't care what your magic is. Besides, we made a promise, remember?"
"But - "
"No buts," the young girl said with an air of authority that seemed at odds with her small stature, "you forget that I have a powerful magic too, I can take care of myself."
"Thank you," he whispered softly as he turned and relaxed into the blonde mage's embrace.
And so, a boy and a girl fell asleep holding each other that day under the Tenrou tree.