Chapter 23, from Yuki rejecting Yuno's willingness to sacrifice herself for his sake, to him confessing his feelings for her, to seeing Yuki and Yuno happily together for the first time. Just don't read the next chapter.
Chapter 38: Akise discovering that the third body in the Gasai residence is the real Yuno puts the fake Yuno on edge, terrified that Yukiteru will abandon her (it doesn't help that she previously more-or-less drugged and kidnapped Yukiteru and nearly killed his friends). Yuki, as if reading her thoughts, reassures her that he won't. He keeps his word in Chapter 39, despite this new information:
Akise: Wait, Yukiteru! She's...! Yukiteru: Akise! Yuno is Yuno!
Chapter 53/Episode 23 shows Yuno killing the Yuno from this timeline, the one he made the promise to stargaze with, as Yuki watches on Pensieve Flashback style. He is horrified at this, and tries to speak to the dying Yuno, but Mur Mur tells him they're only observing past events that already happened, so Yuno won't be able to hear him. She does. Last delusion of an insane, obsessed stalker thinking of her crush in her last moments, or a love that transcends time and space? You decide.
Yuno has just killed/allowed Yuki to fall off a cliff and to his death, intending to repeat the game for a third time so she can continue to be with Yuki. Yuki claws his way back up, his fingers bleeding as he does so, shouting:
Yuki: I love you. Yuno, maybe I'm nothing more to you than a good time to be thrown away. But I... I really cared about you. Your heart knows I'm telling the truth. Yuno, I'll save you! I swear it on my life!
Psychopathic terrorist bomber she may be, but Minene's romantic scenes with Nishijima are overflowing with warm fuzzies.
Yuno may be completely insane and excessively violent, but some of the things she and Yuki do and say to and for each other are rather heartwarming. Admittedly, you may have to look under the horror-soaked Squick to see it.
One specific instance is when Yuno hugs Yuki, shaking and scared after a Near-Rape Experience that he'd just saved her from.
The wedding rehearsal. Yuno just looks so darn happy.
In Chapter 58/Episode 26 when every Diary Holder in the 3rd-world avoids ending up in a Crapsack World. Every single one.
Except for the Third, looks like the Twelfth takes him down. But it`s still better than unceremoniously dying.
Heck, even the Third! He's not off the hook one-hundred percent, but in one of the final panels, you can see him in the veeeery back, outrunning some pursuers.
He gets an even more heartwarming ending in the anime, where the Twelfth, mask off, is seen visiting him in jail, with the two of them having developed a Friendly Enemies relationship.
Yukiteru and Yuno create a happy future. HAPPY END
Paradox has its fair share of heartwarming moments. One of the best in particular comes in the last chapter: Akise has just been run through by Yukiteru as controlled by Mur Mur with a sword that will erase his memories. Akise looks down and out and Mur Mur says that she told him so when she said that his actions were worthless. Then a hand reaches for Akise's and pulls him up...
Tsubaki: It wasn't worthless.
There's also this line, which is a prime example of just why Akise goes out of his way to save everyone:
Akise: The Fifth didn't lose his parents. The Sixth was smiling. Even if you reset, I don't think those smiles had no worth.
Redial has a few of these:
3rd-world Yuno is actually a happy, well-adjusted, normal girl who is close friends with Hinata and Mao. Considering how it ended in the 2nd-world, it's very nice to see them all playing together with a good relationship.
Yuno and Yuki reuniting at the very end. Yuno of the 3rd-world kept having visions of something she was forgetting, and Yuki was utterly miserable for thousands of years without her. Yuno swoops into his world and hugs him and reminds him of their promise to see the stars together. Aww.
2nd-World Minene declines Deus's offer to succeed him in World 3, saying she's happy with the life she's got - she even seems to have copied Nishijima's hairstyle!
Episode 23 has a short one. After Yukiteru and Yuno have Their First Time, they just lie next to each other and share a cute smile. If only Yuki had kept his mouth shut about Aru's final text message...
In one of the omakes, Mur Mur goes out to play, only it starts raining, and Deus goes to pick her up. And when she starts to sleep, Deus TUCKS HER IN. Awwww....
In Mosaic, Minene shows her softer side when she chases 5th across the city, just so she can return his lost dolls.
In the 3rd-world, Minene calls Kurusu to warn him in advance about his son's heart condition, so he can get treatment before it's too late. Deep down inside she really does care, and she keeps her promises even if the world where she made the promise has been wiped out, and there's nobody left to remember the promise but her.
