Gohan was dying.
It was no shock, really. The years had passed, and with each one, Gohan showed more signs of aging. And while the Saiyan in him kept him hair full and black, and his skin mostly fair, his sight began to worsen, his ki steadily weakened, and he began to take on an overall feebler appearance. Piccolo always knew he'd outlive his pupil. He was a Namekian, a long-lived species. Provided someone didn't come along and kill him, he had another couple hundred years left in him.
Alone.
Everyone else with the exception of Dende, Pan, Trunks, and Goten had already passed. And while Piccolo loved his goddaughter, would always be protective of Trunks and Goten, and valued Dende's companionship, it was Gohan who held his heart. And right now, it was breaking.
A year ago, Gohan had been diagnosed with dementia. It started slowly, but now it was in full swing. He didn't remember his brother. He didn't remember his daughter.
But he remembered Piccolo.
And so, Piccolo moved in with Gohan. He helped him bathe, prepared his food for him exactly how Pan had showed him, and kept him company. Gohan would tell grand stories of alabaster and purple tyrants, of giant green bugmen, and of evil pink blobs. Piccolo had once tried to tell him the stories were true, that they had once fought side by side to defeat them, but this only served to upset Gohan as he wracked his damaged brain to remember.
In fact, Gohan began reverting to a childlike state. He began calling Piccolo "Mr. Piccolo" again, and asking when his father would return from space. Where was his mother? Why did he dream of the monsters in his stories trying to kill him? And why, in the dark of the night, did he dream of a boy with golden hair and piercing blue eyes staring at him, beckoning him nearer?
"That's you, Gohan. That's you when you were a boy. Don't you remember?" Piccolo almost pleaded.
"No. I have black hair and eyes."
"You were a Super Saiyan. Do you remember that? You're a Saiyan."
"I don't remember."
That was a couple of months ago. Gohan could barely speak coherent sentences now. Pan, Goten, and Trunks stopped by one last time to say their goodbyes. They huddled around Gohan's bed, where he had been confined after two bad falls in the past couple of days. Piccolo was perched at the end of it, keeping constant vigil. They stayed for a couple hours, just talking to Gohan's prone form. As they left, Pan placed her hand on Piccolo's shoulder weights.
"Thank you, Grandpa Piccolo, for staying with him. I know it's what he wanted," she said.
He shrugged and nodded, not saying anything. She kissed his cheek as she was oft to do, and left. A few hours later, always so attuned to his friend's ki, he began to feel it slipping and then fading. Scrambling from his perch, Piccolo sat on the bed beside Gohan and grabbed his hand. Gohan's eyes opened for the first time in two days and he looked up at Piccolo and smiled.
"The boy is calling to me again," he said.
"That's okay. Go with him. He'll... he'll take you to a better place."
"Oh, okay. I love you, Mr. Piccolo,"
"I love you too, kid," Piccolo choked out.
And then, Gohan closed his eyes and his ki faded completely. With tears in his eyes, though never letting them fall, Piccolo continued holding his friend's hand. Only long after his body had faded to join him in Otherworld did Piccolo move, or even truly register what had happened.
Gohan was dead.
