Stand by Me Doraemon

Synopsis

Noby Nobi is a fourth grader who constantly gets failing grades in his subjects due to his laziness and is always bullied by his classmates Sneech and Big G. His great-great grandson from the 22nd century, Soby, who watches him every day, travels to Noby's timeline while bringing along his robotic cat Doraemon. Soby reveals that if Noby keeps up his act, he will have a disastrous future: he will marry Big G's sister Little G, have his private company burned down, and will be left with a great debt. To circumvent this, he orders Doraemon to help Noby, modifying Doraemon's code to prevent him from returning to the future unless Noby gains a better future.