Heartwarming: The Grim Adventures of Billy & Mandy

  • The end of Jeff's first episode. "Some bugs just can't be squashed."
  • In "The Halls of Time" when Billy turns his dads hourglass upside down when he is about to choke to death.
  • Alot of moments toward the end of "Underfist" surprisingly enough:
    • Fred Fredburger showing just how much he cared about the team.
    • Dracula helping Irwin accept his monster heritage.
    • Jeff and Fred's duet together.
    • Hoss accepting Irwin and even saying his name right.
    • Mindy's Heel-Face Turn.
    • Skarr ending up betraying Bun-Bun, whom he was pretending to betray Underfist for (he spent most of the special hating the idea of the Underfist team, so his betrayal of them seemed so convincing.)
  • In this one from Big Boogey Adventure, when a giant octopus eats Billy alive, Mandy didn't seem to worry.....until later:
    Mandy: (with an unsure look) We don't need Billy anyway....right?
    Grim: (shrugs)
    Irwin: We need to be together!! (cries)
    Mandy: (hits Irwin with an arm for paddle) Billy is....always fine...(looks down to the river and quickily wipes a tear)
  • How about the ending to "Aren't You Chupacabra to See Me?"
    Billy: (tearing up) I-I love you, Daisy!
    Daisy the Chupacabra: (fading) I love you too, Billy (vanishes)
    Billy: NOOOOO!!!
  • Billy finally accepting Jeff as his son in Wrath of the Spider Queen.
  • Billy telling Grim he's his best friend in "A Grim Surprise", complete with a How the Grinch Stole Christmas! Shout-Out.
  • The end of "Loser from the Earth's Core," when Nergal returns home after abandoning his family for half a year
  • Ms. Butterbean is legitimately touched when Billy gives her a gift as appreciation for being his teacher, even though said gift is a rancid apple she eats without bothering to wash and really look at and almost kills her.
  • Mindy's insulting Mandy in the episode My Fair Mandy where Mandy's entered a beauty contest against her. Grim, appalled by Mindy's behavior that actually seems to be hurting Mandy of all people, asks Mandy if she wants Mindy turned into a stinkbug. For all that Mandy's put him through, he's still willing to defend her against insults.
    • Not to mention when the parallel universe is created, Billy and Grim share a surprisingly touching moment as they hug and admit how much they care for each other. Bonus points for it being Grim of all people saying this to Billy.
  • In Scythe 2.0, Grim saving Billy and Mandy from the titular scythe. Doubles as a Crowning Moment of Awesome (with a little bit of Hypocritical Heartwarming thrown in).
    Grim: You keep away from those kids! If anyone is going to have their heads, it's going to be me!
  • In "Scythe for Sale", Irwin unknowingly buys Grim's scythe at a yard sale Billy's holding. And, big surprise, Grim wants to get it back. But, when Irwin goes power-crazy and uses the scythe to brainwash Mandy into becoming his girlfriend, Grim almost immediately seems to become more determined about saving Mandy over getting his scythe back. As aforementioned, even after everything Mandy's put him through, it's incredibly sweet to see him actually worried about her.
  • In the episode Son of Nergal Billy refuses to be Nergal Jr.'s best friend because Mandy is already his best friend, which is kind of sweet in it's own right; but when Nergal Jr. attacks Billy, Mandy immediately comes to the rescue and saves him.
    • Also Mandy is shown in various episodes protecting Billy from bullies and other various dangers
  • Grim bonding with the nuns in Sister Grim.