The spirit world isn't the same with our Chihiro it feels lonelier without her. The other spirits feel it to. Rin speaks softly now trying to not cause any scenes and she avoids all contact with almost everyone it kills him to watch at first until he understands its her coping mechanism kicking in. She'll be back to normal once she forgets the girl.
It's hard to let go of the one girl you love even if you aren't even human. Much less a human spirit. He spent much of his time trying to reach out to her with various things h but he couldn't perfect his magic enough to be seen.
He'd stand and wait at the edge of the river where she'd come and sit. He really wishes she did look back at one point to see him struggle with letting her go. He knew his promise wouldn't be something he could have kept. He was a river spirit not a human boy. Even if he could return to the human world, her world he'd never survive. He knew that. And Haku felt horrible for promising something he couldn't keep. It killed him to watch her wait for him. Frowning he finally managed to reach her some how. A piece of paper and an ink were the only thing separating them at the moment.
He watched her cry and laugh at his little messages until he realized he had to go back. The human world was going to kill him if he didn't go. He could feel the effects it was taking on him. Writing a last message for the beautiful young woman she turned out to be he cried with her as she read the not. She asked him why he had to leave then got angry with him when he wrote he couldn't say. But how could he explain that he was slowly dying from Wong away for so long. If he vanished while on Earth he might not ever return to life ever again.
Taking a shaky breath he wrote one last message for her again this time it really did break his heart and she could see the tear stains that fell onto the sheet of paper. He couldn't promise to ever return but he promises to wait for her until she was ready to come back. Haku felt as if he was torn in two as he returned to the Spirit world. He now understood Why Rin was coping the was she was. It was hard to forget the girl many had loved. It took time for him to heal from the broken heart he had given himself.
He should have known better than to fall for a human girl while she was technically still alive. When the pain finally stopped he took over for Yubaba at the bathhouse when the woman finally needed to get away. He smiled slightly as he went through paper work she had kept for the past thirty years and he came up to Chihiro's. Reading some of the incidents she was in made his heart ache but it made him smile.
Knowing she wasn't perfect made her all that more real for him. On some days he's find himself standing at the balcony looking out over the land. He'd never tell but he had pictured himself with Chihiro talking about everything under the sun. He finally broke down and returned to earth to check on her.
He never made contact but watched from afar and smile helplessly as he watched her move on with her life at one point he managed to get close enough to hear the story she was telling some children. It was the story of them and how they came to be lonely souls still looking for each other. But for the children's sake it always had a happy ending.
Sen and Haku lived happily ever after. He wanted to believe one day they would live happily ever after but with the rapid decay of his soul in the Human world made it hard for him to continue coming. Writing a faint note on a old piece of paper he told her to stop waiting on him. But she was stubborn and had a think skull she yelled out after seeing the note she's never give up on him. That she'd wait until she joined them in the spirit world but one day they'd be together again. Then suddenly there was hope for Haku again.
One day.
One day their fairy tale would come true.
One day he'll be able to touch her again and hold her much like he's wanted to for years.
One day can't come fast enough.
So yeah... Just a little one shot I wrote a while back...