Pretty much the entire Team Squad, really; They've all been through so much trauma and hardships whether it be individually or suffering together with the latest in-universe cosmic crisis...but that doesn't stop them from persevering through in order to (or rather, attempt to) save the universe.
More incredibly impulsive and irresponsible than outright malicious, but Gary could count. Having to re-experience his father's death in Chapter 8 just pushes him farther into the Woobie status rather than the Jerkass variant.
Ash. Throughout her appearances, she's often rude and ill-tempered, with only Fox and later Little Cato as her Morality Pet, but her troubled upbringing is to blame for a lot of it. Even after she takes a flying leap off the slippery slope in season 3, it's more from Invictus playing on her emotions and manipulating her than her actually being evil.
Clarence could actually be seen as one in Season 3. Although his previous actions were absolutely detestable, it can be hard not to pity him as he's now miserably alone (even if it was well-deserved), desperately wishes to atone for his selfish actions, and is greatly upset upon hearing of Fox's death. When he finally gets the chance to redeem himself by helping the Team Squad escape Final Space, he's shot in the back and killed by Todd, who he previously showed pity towards. And to top it all off, the Team Squad decide they want to stay in Final Space to take down Invictus for good, rendering his sacrifice effectively pointless (although he did help several other people escape as well).
Avocato, usually one of the more level-headed and Crazy-Prepared characters, really tends to lose his cool whenever the subject of Little Cato comes up, especially when he's in danger. Episode Six hints that he's also haunted by what he did in the past when working as the Lord Commander's right-hand man. And then there's the reveal that under the Lord Commander's orders he assassinated the King and Queen of Ventrexia, the biological parents of the son he adopted and raised as his own, and never told Little Cato the truth, an act for which he feels so much guilt that it provokes a complete Not So Stoic in him when Gary finds out.
Nightfall, who is even more stoic than Quinn in the main timeline, definitely qualifies. She watched her timeline's version of Gary, the man she fell in love with, sacrifice himself closing the breach to Final Space just after they both watched their home planet get dragged into the breach. Then in her efforts to save the universe, Nightfall spent the next twenty years traversing Alternate Timelines over and over, trying to Set Right What Once Went Wrong, and over and over she watched alternate versions of Gary (and presumably their other friends) die all over again one way or another (usually in Gary's case the exact same way her own Gary died). When she reaches the main timeline, it ends up being the first reality where Gary remains alive, but it's still clear to her that the prime Gary is not her Gary and his romantic feelings are reserved for his world's version of Quinn. But Nightfall refuses to ever get angsty about it — not until that particular episode, where she's pretty much on the verge of a total breakdown.
Little Cato. Dear lord, that boy has been through a lot because nothing seems to ever go right for him. Having been kidnapped by the Lord Commander, he has been imprisoned for 3 years, abused and fallen victim to Mind Rape. He has also been put into multiple life threatening situations nonstop even after he was rescued. Plus when things were starting to look up for him in episode 6, he loses his father.
Mooncake is nothing but friendly and sweet and even though he's capable of destroying planets, he's just an innocent and somewhat helpless Ridiculously Cute Critter who's hunted by the Big Bad for the latter's own wicked ends. There's a good reason why sadistically taking a hold of and draining his powers while the poor guy is visibly suffering is considered Ash's Moral Event Horizon.
Gary cannot catch a breather. His dad seemingly died when he was young, and his own mother neglected him after. In his adult years, he finds himself imprisoned on the Galaxy One for 5 years, with nothing but annoying robots to talk to. Fast forward, his arm is ripped off by an evil alien dictator, and his friend is killed. Virtually all pressure is on Gary to stop the Lord Commander, and he fails pretty hard, even losing Quinn and the Earth in the process. Enter the second season, and things still aren’t looking good for him. He is enslaved by his Sitcom Arch-Nemesis Clarence, and everyone who isn’t apart of the Crimson Light is pretty much gunning for him. The evil Titan god Invictus, who possesses a revived Avocato and severely wounds Gary, an evil maniac named Todd Watson who wants to kill and blame Gary for the destruction of Earth, his criminal mother Sheryl who is trying to steal the dimensional keys from Gary and hand him over to Todd, and so on so forth. Despite all the crap he has put up with, Gary still remains a relatively headstrong fellow throughout the series.
That one Zombie Gary Ash exorcized in The Dead Speak. Dear God, that poor bastard... He died a painful death, all alone, describing it as "drowning in an ocean of Space". His Quinn never came back to save him, and he ended up becoming yet another one of the countless Garys who died closing the Breach, only to become one of Invictus' puppets. The fact that he at least got to die as himself does nothing to erase the fact that he was just as lovable as "our" Gary, and that every single Zombie Gary used to be that same kind-hearted, heroic dork we know and love.
