Hazbin Hotel/Heartwarming

Despite Niffty being a Nightmare Fetishist and not the best maid, everyone at the hotel treats her like their little sister and protect her. Angel saves her from entering an exploitative deal with Valentino, while Charlie in the series finale orders Niffty to stay out of the fight but arms her with an angelic knife to "stab".
Alastor has consistently told Charlie that he expects her hotel to fail, and he's sponsoring it out of pure indulgence. Many acts of kindness in the show betray that he actually thinks differently.

The fact that Charlie keeps a magical storybook of how her parents met and narrates it to herself for motivation.
"Happy Day in Hell" when you see the full context; Charlie is keyed up on realizing she's meeting the angels and that her plan may work. Vaggie tries to curb her enthusiasm by reminding her it's just a meeting, but Charlie dances out into the streets while still singing, much to Angel's amusement. And we see that Charlie really does love Hell, casual cannibalism and all. She sees all the sinners and demons as her people.

Vaggie tries to find a silver lining in the exterminations being moved up, despite knowing it's a long shot. She does give Charlie some hope that they will get more sinners.
The Villainous Friendship that the Vs have. Velvette calls Vox to get Valentino to stop killing her models, and he succeeds. Not to mention that Valentino listens to Vox when the latter points out some logic: Angel may be living at the Hazbin Hotel, but he still has to work for Valentino.
Alastor returns to his radio tower, and he soon gets a crowd listening to his broadcast. Not out of brainwashing the way Vox does, or fear; people genuinely want to listen to him. And he gives a sincere, "Salutations, good to be back on the air."
When Sir Pentious expects Vaggie and Angel to kill him for being a Mole, Charlie has a different idea. She sings to him about what true redemption means, that "It starts with sorry." Charlie convinces Sir Pentious to join her in a duet, and they do a beautiful duet about where his true remorse will begin.

The reason why Charlie puts Vaggie in charge of trust exercises; she says that she trusts everyone, including her girlfriend, but Vaggie is someone who knows what distrust and suspicion are. Harsher in Hindsight when we get to Hello Rosie, but it is a sweet sentiment.
Sir Pentious truly loves the Egg Boiz despite bossing them around; when Alastor returns home, he gives them a tearful hug. At night, he even tucks them in with pajamas and nightcaps!
The fact that Alastor doesn't kill the Egg Boiz or ditch them. He asks them to stand guard over the Overlords meeting, and sends the leader in to listen on Carmilla and Zestial. When said leader tells him about what he overheard, Alastor brings them back to the Hotel unharmed.
- Why Carmilla killed the Exorcist; they were threatening her daughters. And even with that, she covered up the murder because, as she tells Zestial, she doesn't want Hell to go to war with Heaven unnecessarily. It could be an even bigger slaughter, and she doesn't want that on her hands.
Considering how much Husk dislikes Angel for harassing him, it was nice of him to give the BDSM lounge a try. Of course, Niffty had to ruin it.
After their rocky start in the previous episode, Angel ends up saving Sir Pentious during Vaggie's trust exercise of teamwork in warzone. They later laugh about it.

It goes wrong, but Charlie attempts to negotiate with Valentino to get some time off for Angel. When she sees Valentino mistreating Angel, she nearly goes red on him in anger. Angel has to stop her, and it's implied he does it not to save his friend, but to save his boss.
Vaggie mentions that one of the things she loves about Charlie is that the Princess of Hell doesn't act like snobbish royalty. SHe says gently that maybe Charlie could use her princess influence to help Angel.
"Loser, Baby" in full context. Angel has finally opened up to Husk that he sold his soul to Valentino and can only hope that one day Valentino will tire of him. Husk relates, as he says that he lost his soul and overlord status in a game of cards with Alastor. They're both losers, but that doesn't mean they need to destroy themselves with the reminders of their failure.
Husk's first instinct when the shark demons go after them is to protect Angel. Turns out he didn't need to, since Angel reveals he was packing lead. Angel then hands him some firearms.
Angel forgives Charlie for getting him in trouble at work. He understands that she was trying to help, and will respect his boundaries. She starts sobbing in relief.

Lucifer in general. From what we know in pop culture and the Bible, he's supposed to be the epitome of evil. Then we meet the guy: he's a sopping mess who makes and talks to rubber ducks.
- Many viewers expressed on social media and YouTube that they related to him saying, "Take that, depression!"
When Lucifer tours the hotel, he genuinely wants to help Charlie run and renovate it. He points out he could do more good assisting with making the railing safer and adding an aura of luxury. Charlie appreciates it while reminding her dad that getting a conversation with the angels is more important.
Alastor dismisses Husk and threatens him when the latter warns how Mimzy always brings trouble. Then Mimzy lures shark mobsters to the hotel. Alastor handles them without breaking a sweat and tells Mimzy politely to leave, since she used him yet again to clean up a mess. Seems he does care about the Hazbin Hotel.
Lucifer admits why he doesn't want to set up a meeting with the angels: he doesn't want anyone to break his little girl's optimism. In his experience, you can't reason with the angels. They do what they want, and won't listen. Charlie convinces him with a duet that she has to try at least.

While Sera is only nice to Charlie as a formality as she plans to ensure that the Exterminations go on, Emily's niceness is real. She is supportive of Charlie's hotel and advocates for her.
The fact that most of Heaven didn't know about the Exterminations. When Adam opens his big mouth during the trial, there's a collective GASP and the angels look horrified.
While it got her cast out of heaven, Vaggie couldn't kill a child sinner during exterminations. She told the child to run and tried to cover for them.

First scene of the episode, where Charlie is sobbing while lying on her bed, Razzle and Dazzle are by her side holding a box of tissues. Sad and adorable at the same time.
The fact that Alastor of all people snaps Charlie out of her Heroic BSOD and checks on her while Vaggie is too nervous and guilty. Sure, he uses it to finagle a favor from her in the future, but he tells her that not all hope is lost. And he gives her the idea that if they can't stop the Exterminations, they have a plan B: fight back.
Vaggie doesn't mince words when telling the hotel residents that they'll be the first targets of Adam's wrath. She says she and Charlie would understand if they want to find safer places. While Husk and Niffty are obligated to stay because they're Alastor's employees, Angel and Sir Pentious refuse to leave. In fact, Angel recruits Cherri Bomb for backup, and Sir Pentious upgrades his weaponry!
In the middle of Charlie's rant to Alastor, she says she would have been fine with knowing Vaggie was a former Exorcist. The issue is that her girlfriend kept this really big secret from her.

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