Baymax saw this day coming long before Hiro had. It was painful for the robot to watch as the aging male would go about his daily activities.
Baymax would watch as Hiro went to work, tinkering in his lab with shaking hands. He dropped many things. He missed many other things. Baymax had to help out more and more when it came to lifting, putting things together, and with Hiro's aches and pains.
He was almost certain that Hiro knew what was coming. Perhaps that was why he always found Hiro passed out in his lab, working day and night to try and avoid the reality of his mortality.
No amount of work could let him escape the ticking of the clock, and he realized that as he laid in his bed with his large white companion next to him.
Baymax watched with a sadness that he himself could not understand. Perhaps it was his programming causing him to feel regret for not prolonging the life of his patient... Or perhaps he was honestly feeling these emotions.
"It's time, isn't it, Buddy?" Hiro managed to rasp out, and Baymax gave a slight nod.
"I am sorry, but I cannot stop natural death." Baymax regretfully said. Seeing Hiro's shaking form under light blankets made him feel worse for the man's state, so he warmed himself up and laid over the man. "But I can make it less uncomfortable." Hiro chuckled a little, then coughed and was silent for a moment.
"Thanks, buddy. It's been a fun time..." Hiro looked to a wall where his armor hung as a trophy from his youth, and Baymax's gaze followed.
"Do you have any regrets?" Baymax prompted, and Hiro tore his eyes from the wall and to Baymax.
"I should have gone to more botfights." Hiro very seriously stated, and Baymax felt relief that his patient could joke so freely as his life slipped away. The joke was then pushed away when Hiro sadly asked, "What will you do when I'm gone?" Baymax didn't know. Baymax did not have an answer. He should be out helping other people, but this was his companion...
"Remember when Tadashi passed?" Baymax asked. "I will help your family and friends. They must grieve and move on. They are my patients." Hiro nodded, closing his eyes.
"Take care of them all. My kids and grand kids need you, Baymax... Tadashi said you would help a lot of people, and he wasn't wrong." Hiro gasped for air. "Just don't forget about me, Buddy." And with the last bit of his strength, Hiro forced out a shaky statement. "I am satisfied with my care."