- Zorori works at night and starves himself so that Myan, a princess from a video game, will enjoy her time in Zorori's world. Note this is not at the princess's insistence, but instead Zorori hides what he's doing from the princess so that she doesn't worry about him. The princess gets properly upset at Zorori's suffering for her sake.
Myan: "To me, you'll always be my Sir Hero."
- Zorori and Myan when they meet in the park at the end of that episode is both touching and tearjerking.
- The end of the Monster Major League arc, where the super-strong, super-aggressive, and rather asocial Gojimatsu realizes what it means to be part of a team when Zorori bats a 300 mph baseball with his tail at the bottom of the 9th with two outs just so the monster could have his chance to bat.
- The end of the second Cinderella episode in the third series, where Zorori gives up a practically guaranteed shot at his life's goals so Cinderella can be happy with the real prince.
- Something similar also happens in the second Puss in Boots episode.
- The second season's first ending,"Mama no Komoriuta" (which means Mama's Lullaby).
- Bonus, here's the full song.
- In Episode 40 of the first series, Zorori and co. are trying to infiltrate a mint in order to print money and become rich, so Zorori disguises himself as a delivery guy and devises a plan to distract the mint's sole security guard. The ensuing night spent with the guard is actually pretty sweet, wherein he chats with Zorori about his granddaughter whom he loves dearly, and ends up being thrown a party for his (upcoming) birthday, all of which he enjoys quite a bit. What really hits home just how much he appreciated Zorori's company is when he believes that Zorori's been injured (though he really isn't), and immediately tries to get medical attention. He even has the police restrain Zorori because he doesn't want him to over-exert himself before the ambulance arrives.
- The conclusion of the episode that introduces Mecha-Ishishi and Mecha-Noshishi has them part ways with Gaon, their creator. What makes this heartwarming is that they're not doing it because they don't want to travel with Gaon, but they feel like they're not worthy of it yet, so they decide to embark on their own journey to become experienced travelers like him, in hopes that the three of them can travel together on equal terms. Gaon sees them off with nothing but happy regards, and even Zorori (who has no real feelings towards Gaon whatsoever) openly believes that they'll all make a happy group of companions one day.
- The fourth ending of the first series, which is a recap of various episodes, offers a nice little conclusion to this. There's a still image of the two robots having returned to Gaon, having brought him lots of different packages from their travels. All three of them are smiling, too!
- Zorori loves his mother so much that, knowing good and well how much punishment it could bring upon him, he's willing to escape from Hell and sneak into Heaven just so he can see her! And then he goes back to Hell to demand his revival just to make her happy!
Heartwarming / Kaiketsu Zorori