The young exorcist, Allen Walker, could be seen returning to the Black Order through an Ark gate after completing a mission.
Man, I can't wait to get something to eat, I'm starving! He thought to himself not noticing himself rub his stomach. Allen Walker was currently alone with only Timcampy as his companion, Link had told him that he needed to report to Leverrier so Allen was free to go back as long as he remained supervised. Sighing to himself he reluctantly walked to his room seeing how his fatigue was hindering him more than his own hunger. Being so distracted he didn't notice that no one had greeted him and even if he did he wrote it off as them being busy. As he lied down on his bed he found himself remembering one of his first memories he had in the Black Order. And before he realized, he fell asleep as the memory became a dream.
When Allen Walker first arrived to the Black Order he was met with hostility (thanks to a certain samurai), he originally thought that people would be afraid of his disfigured left arm an thought he would be cast out. He was proven wrong when he saw how they had put a party together for him. He still remembers that day.
"You really thought we'd let you join us without a welcoming party?" Reever asked Allen.
"Everyone was up all night getting ready." Jeryy told Allen.
"That's why I was acting weird today; I didn't want to spoil the surprise." Lenalee had explained for her earlier behavior.
"Welcome to the family Allen, you're with us now" Reever told him.
As everyone welcomed Allen, he remained slightly shocked from everyone's welcomes; he was hit by a nostalgic memory with Mana.
"Welcome back son." His father told the younger Allen. Regaining his bearings, Allen smiled genuinely ass his
"It's good to be back." Allen said with tears in his eyes and with a tender smile.