An understated example, but in the first episode/volume, Aqua tries to get money for adventurer registration by asking for money from a priest from the Eris Sect. While he chides her for claiming to be the goddess Aqua, he gives her the money anyway as a gift. Given that we eventually see how difficult life in this world is, how many adventurers live a hand to mouth existence that requires they save every coin, how annoying Axis cultists could be, and how they seem to deliberately go out of their way to harass the Eris Sect, and how the priest must have thought he was dealing with an Axis cultist that was even more deranged than usual, the fact he still gave her enough money to register was very kind and generous, especially since we never see him coming back to ask for the money, even when the protagonists are rolling in millions.
Despite getting off on the wrong foot, Kazuma and Aqua are shown getting along very well in the hard-work montage: toasting each other every night and smiling while they dance with their co-laborers. At the end of it, and Aqua thinks Kazuma needs to use the restroom, she offers to go with him because it is night. She sounds sincere when she does it.
Kazuma and Megumin bonding over the beauty of explosions. It's pretty interesting to see such a guy like Kazuma, who can be quite callous on his partners, behave this playfully with Megumin because of this.
When Darkness is given a death curse due to Megumin's actions, she and Kazuma immediately come up with a plan to storm the castle of the one responsible to get him to lift it. While Aqua simply dispels it, rendering their effort pointless, it still showed that they were willing to go towards their potential deaths to save her.
The fact Aqua dispelled said curse without a second thought or being asked. Yes, she wasn't asked because nobody knew she could do that yet, but it shows how quickly she's come to think of Darkness as her friend that the normally lazy and selfish Aqua would immediately save her.
After the completion of the Lake Purification quest involving alligators wrecking the cage Aqua's in, for once, Kazuma and his team praised Aqua for her persistence and stated that she deserved all the reward for herself (basically letting her indulge in her usual selfishness), despite Aqua being too traumatized at the experience to acknowledge this.
After losing his life to the Winter Shogun, Kazuma has an audience with Eris and is offered to reincarnate back to Japan. He's more than pleased with this and begins a long rant over the absurdities of his party, only to unconsciously shed a few tears, realizing that he's grown fond of the girls and doesn't really want to abandon them. On top of that, when he wakes up on Aqua's lap after she's done reviving him, Megumin and Darkness immediately jump on him for a hug and, if their voices are anything to go by, they've been crying a lot thinking they've lost him for good.
In Chapter 16 of the manga\Episode 8 of the anime after all the spirits are exorcised from the mansion, Kazuma shows respect to the ghost of the girl that was haunting it by cleaning her grave stone. And at the end of Episode 9, Darkness finds him sweeping her grave implying that he does it on a fairly regular basis.
Kazuma defending the Succubus in Volume 2 / Episode 9. The light novel gives a bit more insight into why he did so: namely that he couldn't betray Keith and Dust's trust by exposing the truth, nor let the succubus (who was doing her job) be killed. He got his ass kicked, but deemed it worth it.
Aqua doing her duty as a goddess and laying Keele to rest in Volume 2, after he turned himself into a lich to be with his beloved in her final moments. She comforts him by assuring him that she died content with him by her side and then puts him to rest. Even Kazuma was moved by Aqua's uncharacteristic gentle warmth and kindness, before sarcastically wondering to himself: "Is this really the same stupid and useless Goddess that I know?"
Aqua: Arch wizard Keele, you forsake the laws of the god and became a lich by your own conviction. In the name of the goddess of water Aqua, I absolve you of your sin… When you wake up, you will be before a goddess with unnaturally large breasts named Eris. If you don't mind the age difference between you and the one you love, or if your relations are not between a man and a woman, and if you wish to meet her no matter what form it may be in… You can try asking Eris. She will make your wish come true."
Anytime Aqua acts like a goddess, really. In Episode 9 of Season 2, Aqua genuinely treats her followers well and only want what's best for them. She even goes so far as to try and purify the hot springs because she doesn't want them to get sick from swimming in polluted water, even though this means shoving her arm in acidic water. Considering how she normally acts, it says a lot that she cares for them despite them not believing her.
When Kazuma is imprisoned for aiding a member of the Demon King's army and awaiting trial, at the beginning of the season 2, Aqua offers to arrange a jail break so he can escape. Willing to give up everything she currently has going for her in exchange for a life on the run in order to help him. Considering what a spoiled brat and absolute meanie Aqua can be this is a monumental sacrifice and shows just how much she really cares about her friend. While he turns her down Kazuma silently acknowledges this as well and is deeply touched.
In Season 2, Episode 4, Darkness uses one last move to get out of the arranged marriage with Alexei and tells everyone that she is pregnant with Kazuma's love child (unnecessarily it turns out as everything's already been settled). Darkness' father's first reaction is to begin to bawl in happiness in finally getting his first grandchild. Taking into account that Darkness is telling her father that she is pregnant out of wedlock to a no-name adventurer, his reaction of extreme happiness in finally becoming a grandfather is so awesome and shows a lot of what kind of a man and father he has been.
In the aftermath of the Lizard Runner Quest, it becomes apparent that Kazuma's deaths are harder on his party members than they are on him.
Upon "waking up" in Eris's audience chamber, Kazuma's first concern is the safety of his party, and is pretty chill about being dead.
Aqua has a vested interest in keeping Kazuma alive, but she doesn't look like she's in a temper-tantrum when Kazuma revives and is instead uncharacteristically calm.
The end credits after the anime episodes, especially from season 2. They feature the party members doing everyday things from Aqua entertaining children, Megumin playing with Chomusuke, Darkness playing with a girl with Chris joining in and Kazuma fishing and preparing a meal for them. This while the voice actresses of the main girls are singing a soothing song. Very adorable for a comedy/parody series.
The 1st OVA has Kazuma wear a choker in Wiz's shop, only to learn that it will slowly strangle him in four days if his wish isn't granted (it's supposed to keep women serious about losing weight). While the episode mostly focuses on his sexually demeaning demands for the girls, there are a few heartfelt moments.
Yunyun asks Megumin why she's so determined to save Kazuma, even with all the humiliation he's putting them through. Her stated reason is needing someone to carry her home after her daily Explosions, but the main reason that she keeps to herself is simply gratitude toward him for putting up with her for so long after several other parties kicked her out for being too much of a burden.
By the fourth day, when the choker still shows no sign of loosening up, Kazuma comes to terms with his impending demise, and expresses both gratitude and remorse toward the girls for putting up with all his kinky demands. They all embrace Kazuma, and he finally feels true peace... which was actually the wish he obliviously gave the choker. Of course, Mood Whiplash sets in once he starts apologizing to them for disgusting sexual thoughts before he dies, not realizing that the choker has already opened.
In the movie, which expands on Volume 5, Aqua says that Kazuma still has the craziest ideas she's seen. Kazuma simply says that's because he has a goddess on his side and calls her his partner, this makes Aqua smile.
Additionally, after Kazuma has been psychologically scarred due to the lady orcs almost raping him, Aqua puts him on her lap, stroking his hair and softly trying to calm him down and tell him that the scary event is over.
When it's told in the prophecy that his and Yunyun's son would go on to defeat the demon lord, Kazuma looks both worried and proud at the idea of his son doing that.
At the end of the movie, Megumin ask to be of more use to the team, so she gives her card to Kazuma so he can add her points to any stats he wants. Because it makes her happy, he doesn't waste a second in spending all the points on explosion magic, and lets her fire off a spell without ever telling her what he did.
How Darkness and Chris became friends. Darkness was a lonely but devout girl who went to the local church of Eris every day praying for friends she could go on fun adventures with. One day, she meets Chris on her way back from church. What really makes this heartwarming is that this is Eris, Darkness's goddess herself, personally answering the prayer of a lonely little girl. And unlike in other media, it's not so that Darkness will become her champion or chosen one or to fulfill a prophecy for her. It's because a young girl who'd lost her mother really, really needed a friend.
In Volume 6, Kazuma's party is invited to dine with Princess Iris so she can hear about their achievements. Darkness is very reluctant to let them meet the princess, fearing that their lack of etiquette will reflect poorly on the Dustiness house and even get them executed. Iris is initially very condescending to Kazuma, refusing to even speak to him directly and casting doubt on all his exploits, particularly his victory over Kyouya. When her insults go too far, Darkness discards any concern about her reputation and finally smacks Iris on Kazuma's behalf.
Kazuma in Volume 7. Considering that he was willing to marry Darkness off, the first time a suitable suitor came along (Alderp's son, who, despite all expectations, is actually a very decent human being), the fact that he spends much of the volume desperately trying to raise the two billion eris needed to pay off her debt so she wouldn't be married off to Alderp, is truly touching. Especially the part where he breaks down and says "It! IS! NOT! FINE!" when Megumin pesters him about "ignoring" Darkness one time too often because Kazuma really couldn't come to her aid if she didn't specifically ask for it.
In the eighth novel, Kazuma and Aqua eavesdrop a conversation where somebody was trying to make Megumin buy a white powder that gets really addictive after you try it once. He immediately kicks the door open and starts hurling threats to the sellers, including using his fire-starting spell to "burn those damn things away", and an unusually-silent Aqua rushes pass him and punches the first guy she sees on the face. As expected, it turns out to be a misunderstanding (the white powder in question was something you mix with water to get the local variant of chewing gum), but watching Kazuma and Aqua drop the usual silliness and barge in completely willing to fight against what they thought were drug dealers for Megumin's sake was a sight to behold.
Volume 11 drops a doozy as Megumin basically asks Kazuma to be her boyfriend in the epilogue.
In Volume 9 there was her love-confession and the unusually serious conversation about both hers and Kazuma's past.
Volume 10: Given how poor their relationship was in volume 6, it can be somewhat heartwarming to see Kazuma and Claire join forces to protect Princess Iris from an Arranged Marriage. In fact in stark contrast to volume 6, it seems that Claire is the only one unopposed to Kazuma's appearance in the capital and treats him with a higher level of amicability than in her first appearance... sometimes.
Volume 15:
Aqua is reduced to the brink of tears when a wounded adventurer refuses to be healed by her instead of Serena note A high-level female priest who arrived in Axel this chapter, whom ends up usurping Aqua as the Guild Hall's "mascot", as all the adventurers start flocking towards her. Turns out she's actually one of the last remaining Demon Generals, who just so happens to be a human priestess of Regina, the Dark Goddess of Puppetry and Vengeance, who is brainwashing all the adventurers in the town to become her slaves thanks to the favors she does for them., since her healing magic is the one thing that everyone, even Kazuma, acknowledges she is good for. Kazuma responds to this situation in a way befitting a man of his caliber: sprinting up behind the priestess and delivering a missile dropkick to her face, in spite of knowing her "aura of Vengeance" power would immediately reflect the damage back to him rendering them both unconscious, on top of inciting her wrath as a Demon General and the possibility of being directly targeted by the Demon King's army. Because, even after all the headaches she causes him, the debts she racks up, her laziness, rudeness, and incompetence... seeing someone else make Aqua cry for something that, for once actually wasn't her fault, is something that Kazuma simply will not stand for.
Near the end of Volume, when Aqua asks Kazuma if he's ever regretted being reincarnated into this world, Kazuma sincerely replies he doesn't and is in fact grateful for it, despite everything. Aqua's reaction is one of relief, leading Kazuma to wonder if part of her felt guilt over roping him into this.
Volume 16:
Earlier in the volume, Kazuma, Vanir, and Wiz enter a dungeon to help level up Kazuma's skills after being reduced back to Level 1 following his skirmish with Serena. During this expedition, he finds a jet-black suit of armor that he ends up gifting Darkness as a souvenir. However, when Megumin asks if he got anything for her, Kazuma says he didn't.
Later, while going off to find Aquanote who had departed on her own to fight the Devil King, he makes up for it by gifting Megumin a large rucksack's worth of top-grade manatitenote Magic crystals for adventurers as an alternate means to fill up on mana for her to unleash multiple Explosion spells upon the Devil King's castle barrier. What takes the cake is that he even tells her that he's counting on the strongest mage in the world - her. With that, Megumin runs up to Kazuma and wraps him with a hug.
In the same volume, during the scene where it looks like Kazuma is finally going to have sex with Megumin, Kazuma stops himself from going all the way because Aqua isn't around to ruin the moment. More specifically, Kazuma wants everybody to be together when he does the deed, even with the likely risk of Interrupted Intimacy. Showing that even as desperate and perverted as Kazuma is, he still values his True Companions more than anything. Of course, he ends up immediately regretting this action but it is still a touching sentiment that even Megumin seems to appreciate.
Volume 17: Kazuma finally defeats the Demon King with a point-blank Explosion, destroying his own body in the process. Eris offers to let him relax in Heaven, live in luxury back in Japan, or regain his body in the parallel world. Without hesitation, Kazuma chooses to return to "that good-for-nothing world" and all the friends he'd met. Aqua, finally back to Heaven after getting dragged down against her will, is now eager to abandon it to accompany Kazuma once more as his "cheat" (though he chooses Eris to screw with her). Aqua later finds an opportunity when she and Kazuma are alone to sincerely thank him for his help, with Kazuma remarking that her smile at that moment was the first time she'd ever made his heart skip a beat.
Spinoffs
In first volume of Vanir's spinoff, Wiz gave up her humanity and adventuring career to save her comrades from Verdia's curse. In the epilogue, she reunites with her two of comrades, who got over their Unresolved Sexual Tension and got Happily Married.
Case in point.◊ That's the daughter of her two comrades.
In the first volume of Megumin's spinoff, she confronts her two classmates who tricked Yunyun into giving them money.
The next volume reveals they were actually telling the truth about the sick brother and they give Megumin a farewell gift as thanks for the healing potion she made.
In Megumin's spin-off, Megumin was trying to save up money to leave her home village and was talking to Yunyun. Much like the "drug" incident, she spoke about possibly needing to "sell her body" and the way she described it made Yunyun think rather indecent things. By the end of it, Yunyun was going to burn the person who was "using" Megumin. Turns out Megumin was just being a potion tester, but like the "drug" incident, it says a lot about how close Yunyun and Megumin are that Yunyun was willing to defend Megumin.
◊ That's the daughter of her two comrades.
