Grumpy Bear: Anime and Manga
- Sailor Moon: Haruka Tenoh and Michiru Kaioh. Sailors Uranus and Neptune believe that victory cannot be attained without some horrible angsty sacrifice that only they have the moral strength to make. The idea that The Power of Love And Justice could triumph with minimal unpleasantness seems to offend them on some deep level.
In the manga, it's explained that they basically were ordered by the Queen to live alone in their individual castles at the far reaches of the solar system while the kingdom was destroyed. When they abandoned their posts to try to find the Queen, they accidentally summoned Sailor Saturn and destroyed all of existence. That would pretty well explain their loner natures and pessimistic attitudes (wanting to save their home and all). This is also why they become a lot more social and friendly after that arc, when they learn that Saturn is not just a force of destruction and decide to raise her.
- Seto Kaiba of Yu-Gi-Oh!, the Ineffectual Loner and staunch advocate of independence, self-reliance, and individual strength, which makes a lot of sense when the only way to save the world is by winning a one-on-one match in a child's card game, but no sense when The Power of Friendship rules.
These traits were recycled into Edo in Yu-Gi-Oh! GX, who not only strove to be an Anti-Hero, but seemed to think he was Batman. This was because he thought he was a slave to his fate; pity for him that the season's theme was Screw Destiny.
- Piccolo from Dragon Ball. He believes Goku is too soft and kind to be a true warrior. Later villains like Raditz and Vegeta try to replicate this effect, but they become less and less out-of-place as the story continues.
- While the world(s) in Tsubasa Reservoir Chronicle aren't exactly clouds and rainbows, Ninja Kurogane starts out as one of these with little regard for human life and something of a temper, but as he gets closer to his True Companions this gradually fades. In later chapters he's even sacrificed his arm to save Fay, indicating that he's fully defrosted.
- Yue (Cardcaptor Sakura) is another CLAMP example. Though somewhat hard to pin, his stoicism, bitterness, inability to let go, and the fact that he has no qualms about beating the ever-living daylights out of a ten-year-old girl make him rather a grumpy bear.
- Zelgadis Graywords of The Slayers fits this trope fairly well. While the world he lives in is far from perfect, he is the most cynical member in the group of exuberant nut jobs he travels with. A group which he has tried to part ways with on several occasions, though invariably ends up traveling with anyway.
- Rossiu from Tengen Toppa Gurren Lagann becomes one after the Time Skip. But it's a bit more complex, since he isn't just on the wrong side of the Sliding Scale of Idealism Versus Cynicism. Tengen Toppa Gurren Lagann is a Hot-Blooded Super Robot Anime, but he thinks they live in a gritty Real Robot Anime. So his actions are interpreted by some fans of the show as a Jerkass instead of a cynic.
- Toshiro Hitsugaya from Bleach. You know you're this trope when one of your nicknames is "Captain Grumpypants".
- Evangeline of Mahou Sensei Negima! counted as this, at least earlier in the series. As of late, the Genre Shift into action shows that her attitude may be somewhat justified.
- Fujimoto from Ponyo on a Cliff by the Sea is a jaded, cynical human-hater who assumes the worst. He lives in a world that is about as idealistic as possible, and is married to an Anthropomorphic Personification who distinctly resembles the Blue Fairy in demeanor. Hilarity Ensues.
- Kyon from Haruhi Suzumiya. Always negative about everything... when most people would give anything to be in his position.
- ARIA has Aika, who for the largest part doesn't seem to realize that living as an apprentice-undine on Aqua is the next best thing to paradise.
- Which she might have gotten from her teacher, Akira. At least Aika wasn't that way when she was a kid.
- Meta Knight in Kirby of the Stars. Fumu calls him out on it, but she eventually gives up.
- Knuckles from Sonic X. Justified in that he's a loner who guards the Master Emerald in Angel Island and has a bad temper which makes it impossible for him to cheer up. Even his own friends doesn't help any matters.
- Kamisama Kiss is a Romantic Comedy that tends to be light-hearted and very optimistic. The male lead, Tomoe, is a Deadpan Snarker with a pretty cynical attitude.
- Usahara the rabbit from Damekko Doubutsu is not only aggressive. But he's the only character in the series who doesn't act very happy and would usually attack others when they insult him.
- Naofumi of Tate No Yuusha No Nariagari is bitter after being betrayed and robbed at the start of his adventure, only smiling when he contemplates another's misfortune. It's a good sign that his mind is being warped by magic when he starts smiling and being friendly.
- In Guardian Fairy Michel, Biam is much nastier and grumpier than the other fairies, which leads to his working for the bad guys.