Terra
Eraqus had gotten a notification from Yensid, that there was a young keyblade wielder in the streets of an unknown world, and in need of a home. So, he got on his rider and went to this unknown world.
he found the boy, starving, cold, and indeed, just as Yen Sid had said, homeless. Figuring the boy didn't have much to lose, Eraqus scooped the boy up and wrapped him in a blanket that he had brought in case of a situation like this.
The kid didn't protest as Eraqus wrapped him up. He slowly fell asleep in the warmth of the blanket that encased him. One of the locals spotted him. "Are you sure you want to take a freak in?" He asked the keyblade master.
"He is a child, is he not?' Eraqus asked. "He will be welcomed into my home." The local scoffed.
"Then, you've welcomed a freak into your home." The local replied.
Eraqus brushed it off as the local's intolerance of magic of any sort.
Taking the young child back to the Land of Departure, he nursed him back to health. The child didn't say anything to Eraqus, No matter how much he urged him to.
A few years had passed, and Eraqus had learned the child's name was Terra. And he was an exceptional fighter but had trust issues. He continued to remind him that he could trust him. As Eraqus saw Terra as his own son.
Aqua
Once more, Eraqus had gotten a notification that a young key bearer was in need of his help, and a home, on an unknown world.
So, once more, he had hopped onto his glider and journeyed to this unknown world. Much like how he had found Terra, the girl was starving, but since it was a warm summer day, she wasn't freezing. And although she had tried to protest when he bent down to help her, she couldn't.
"It's alright, child." Eraqus said. He brushed the gurls blue bangs aside, her blue eyes were dull and lifeless. Her cheeks were red due to hunger, and heatstroke.
"W-who are you?" The girl asked.
"My name is Eraqus." He said the girl struggled to keep her blue eyes open to greet him in return.
"Aqua." She rasped out. She coughed and gasped for air.
Feeling sorry for the girl, Eraqus put her under the sleep spell. It worked, Aqua had fallen asleep, and her coughing fit stopped. Picking her up like he had done with Terra all those years ago, he took her to the Land of Departure.
Upon arrival, Terra greeted his master. Only at the last minute did he notice the blue bundle his master was carrying.
"Who is she, master?" He asked.
"Aqua." Eraqus replied to the boy he had grown to see as his own son. "She needs our help, Terra."
Terra nodded and rushed to get some water and helped his master get the girl settled into Eraqus's room.
Dismissing Terra, the keyblade master watched as the girl's breathing became more uneven and labored. "I am not a freak." She muttered in her sleep. Tensing, remembering back to when he had brought Terra home for the first time, he whispered encouragingly;
"Of course your not."
A few years have passed, and now Terra and Aqua were close friends. And a fine young man, and fine young woman. Eraqus couldn't have been more proud of his students.
Eraqus noticed that whenever one got hurt, the other would stay by their side, and make sure the other was cared for properly.
And if he didn't know any better, he'd say they almost had a crush on eachother. Soon, Ventus came into his care. And Terra and Aqua took turns in caring for the young comotose boy.