Just hearing the Aurin speak is enough to make your heart melt. They're just so unbearably cute it's impossible not to hug them! (Bonus points: they're all about hugs.)
... Well, that, or drive you to murder each and every single one of them. They're very, very polarizing.
Lopp. Friendly, energetic treasure hunters that are essentially a bipedal race of sentient, 3 feet high rabbits. You're laughing at the sheer hilarity, you're wanting to hug them, or experiencing both at the same time.
Playing kickball with the Stormseeker children in Ellevar. It makes your unintentionally delivering poisoned supplies to them all the more poignant and painful.
You can pay your respects to Queen Myala Everstar via the Royal Pillow. The poor girl could really use a boost.
Pretty much all of "The Making of a Matria." From Myala believing in Yaenna's abilites, to the PC assisting her every step of the way, to the never-ending celebration once the arc is over.
The interactions between Artemis Zin and her friend and bodyguard Kevo are surprisingly sweet. Despite the Little Miss's reckless attitude and propensity for launching herself straight into danger in the name of ratings, the Draken really does care about her, and she him.
Curing Sadie Brightland on the Exile Arkship, the Gambler's Ruin. In the midst of all the death and suffering from major cryopod failure, you at least save a life and one on its way.
Only to have that bright point destroyed a few levels later.
In spite of their fundamental differences, the Aurin and Mordesh are the best of buds. It's a consistently strained friendship but both will rise up for the other.
Bringing back the skull of a weird animal as a gift for Victor Lazarin. It's oddly adorable how excited he gets. There are two opportunities to do this, and in one of them he seemingly notices it and perks up before you've even said anything.
What is that you hold in your hands? Can it be the cranium of some contemptible creature? Please, allow me to appraise your discovery!
Victor Lazarin comforting his daughter at the end of the Everstar Grove arc. Should have figured he'd be the kind of person to advocate moving forward in spite of bleak, seemingly hopeless odds.
Optimism strikes again after the Squirg episode in Whitevale, this time towards the player character.
Victor Lazarin: The evacuation commences. Now we will put these wicked woes behind us and look to our future on this fantastic planet.
A group of three exile ladies (a human, an aurin and a granok) trying to cheer up to a depressed mordesh in the bar on the Exile Arkship. From the conversation, it appears someone teased him about his top hat.
Granok: You tell me if anyone troubles you, hun. We all come from somewheres different.
Aurin: We think you are so special, okay?
Granok: If you don't feel like takin' the hat off, don't take it off!
Human: I think the hat's great!
Granok: Listen, sweetheart, you can't go fallin apart when stuff like this happens.
Aurin: Such a pretty hat, but it's what's inside you that is truly beautiful.
Finding Hunter Joresh and his new Kurg, Nelly, in Malgrave. Up until this point, Joresh has been portrayed as a law-bender interested only in profit, but now one of his quests involve making his new pet happy, and the rest are done by you so he doesn't leave her side. It's very sweet, how much he cares about her.
It's a subtle thing, but dialogue options becoming less formal and more familiar around characters you repeatedly interact with. For example, between Exile player characters and Victor Lazarin.
Player Character: I'll be seeing you, Victor.
Victor Lazarin: Likewise. I expect to experience more of your endeavors before too much time expires.
Though in Victor's case this becomes more of a tearjerker after Lucy dies. Your friendship is one of the few things he has left.
As your reputation grows, minor characters will start acting star-struck and flustered when you meet them. Which is very rewarding after all the effort you've put in to get that far!
In Grimhold, you can rescue a slank caught in a trap and heal its wounds. Once you return to Belabog Quarantine, you can see it a Mordesh has taken it as a pet. The new owner even has a story about how the brave little guy bounded out of the quarantine, a real miracle...
The Caretaker finally starting to have faith in you, after you've consistently defied the odds in the Bio-Mech Facility Alpha.
I have found that the odds are not always what they are cracked up to be.
Drusera's words to you before she leaves. Doubles as a tearjerker.
Drusera: You are precious, and I don't want the Entity to harm you. Farewell!
At the Defile, Avra Darkos lightens up enough to dance with the player character. At a gig for the 'Flower Puff Girls', no less.