[TLDR in the End]

May some relationships may remain forever. But like everything, relationships will fall apart eventually.

And that's what Hope believed. Emery was doing well for herself and the Prodigal treats her well. And so what was Hope's role in her life? There was no need for him to be in her life; when he had his own to life to follow accordingly.

Hope thought he didn't love her anymore. And she realized that the hard way. His eyes were emotionless everytime he whispered "I love you" and his arms around her grew cold. Soon enough, all that warmth that was supposed to be saved for her, were given to someone else.
He knew he broke her little heart, but there was no point in stopping her if he didn't feel a single bit of sorry.

But regardless she wished him goodbye. It was useless, when they were going to see each other the next day.

He was wrong.

++++++

"She's probably away for a few weeks. She's fine-"

"Hope, I don't think you get it. She's gone." The words left Chanse's lips as he forced his way to Hope's conscious. 

Perhaps it was the final realization, but the words that were supposed to come out of his mouth... he couldn't hear them at all. His eyes were blank and confused as he was too busy reading his best friend's lips.

"She's dead."

He's never been so wrong in his life to a point to know his mind is wracked with guilt and a heavy heart.

Hope thought he didn't love her anymore. He thought.

Sometimes you gotta lose somebody,
Just to find out you really love someone

He didn't expect the lyrics of one of her favorite songs to really hit him. The song was right; but for sure they didn't mean it. Not like this.

++++++

It was as expected after her death. The event affected him gravely.
It was Chanse's idea to stop teaching, knowing that eventually his eventual sorrow character would only affect the children - he'd be fired soon after.

Kirisawa took this opportunity to focus on his art but his style would progressively grow weary and dark. He'd try to play the piano, but his fingers cramped after the flash of images invaded his brain.

So many sleepless nights that he eventually had insomnia; he decided he'd focus more on the Prodigal side of things. There, he worked endlessly to make sure he wouldn't have to go home alone to deal the nightmares head on.
Though the hard work did pay off. With Maximille growing weaker from his older age - the Overseer appointed Kirisawa as the Arbiter...

... and not for very long.

There was news that they've appointed a new Grandmaster. A brand new Overseer. Its former one appeared out of the shadows; Grandfather emerged to claim the Arbiter title as his own. And leaving Hope without a proper title, but still considered a Headmaster.

++++++

He didn't understand as to why Grandfather disfavored him so much. Neither did the rest of the Headmasters, but no one dared to step further than what the Arbiter demanded. Atticus blatantly ignores all of Hope's statements and suggestions, and often threatened him by removing out of the Headmaster position.
But every attempt Grandfather would do against Hope, the Arbiter's decision would be opposed by Overseer. As to why? No one really knew.

Except for Maximille, who's been watching Hope from his bed...

Away from Grandfather's eyes, Maximille needed to take all possible actions and help direct Hope to someone that can help Hope from Atticus's threatening aura.

From there, he found his way through a maze of people. Through several hallways and several doors. Max claimed that finding them was difficult enough, but Hope needed to see them before he'd be kicked out of the Prodigal in no time. He opened the door to one of many bedchambers in the manor, with a single individual on the balcony.

The sight of them made Hope's life turn around instantly. He didn't recognize the young woman, but the mismatched brown, gray eyes gave it away.

"It's been awhile," she said. 

++++++

She was never dead the whole time. And it pained her the most that she's hid herself away from him and supposedly faked her own death, when all the sleepless nights and emotional damage were all for nothing. However, she did emphasize that she really did want to rid of herself.

"Apparently Atticus had stopped me before I could even pull the trigger," she explained. "He was watching me for a long time and that I was his target."

For the rest of the night she had explained everything from when Grandfather intervened all the way to Grandfather taking the Arbiter title away. His supposed jealousy only brought hate towards Hope's progression and that Emery needed to force her way into stopping Atticus from making any brash decisions that were driven through emotion.
She could only promise Hope that Grandfather won't be abusing his power against Kirisawa anymore. Other than that, she couldn't promise anything else. 

A kiss on the cheek was the only thing she could spare before she left the radar once again.

A tear ran down his eyes when he was alone once more. Whether it was because he was happy that she forgave him and still loved him. Or it was perhaps that Hope wasn't going to see her again?

TLDR

- Hope broke up with Emery because he didn't think he loved her any longer.

- Discovered that Emery died from attempted suicide, caused Hope to become emotionally distraught.

- Stopped teaching as he was mentally drained, which affected his performance greatly. He took up painting again and composed music.

- Continued to work in the Prodigal, made his way up to the Headmaster position. Originally was supposed to be the Arbiter, but was taken away by Grandfather, who claimed the position as his own.

- Constantly being harassed by Grandfather, threatening that Hope would lose his position or even get kicked out of the Prodigal if he did anything "wrong."

- Maximille brought Hope to Emery, who Kirisawa discovered to be the new Grandmaster/Overseer. She's also has been alive this whole time.