In Rondo of Blood, the moment when Richter is reunited with Annette and they embrace each other is quite touching. The moment is just as sweet in the remake, even with the campy voice acting.
Most of the best endings in the series are remarkably warm and optimistic, making them especially satisfying to achieve considering the series' otherwise grim tone and abundance of tragic moments.
Symphony of the Night has Maria chase after Alucard, hoping to ease his pain of loneliness. Richter even encourages her to go after him... And she succeeds!.
After a whole game of brainwashing and fighting one of the most horrifying aspects of Dracula, Harmony of Dissonance has Juste, Maxim, and Lydie finally all together again and happily chatting as if it was another normal day. This ending is made all the more sweet given how sad the game's othertwo endings are.
Dawn of Sorrow is the last game in the series chronologically, and barring a bit of ominous dialogue it is easily one of the happiest with Soma reuniting with all his friends who are all elated to see him alive.
Across all Castlevania games, Death is a reoccurring character and is always working with Dracula. Why, you might wonder? Some dark desire to see all life snuffed out? Some unknown rite binding Death to Dracula's servitude? A lack of other hobbies? Nope! Dracula and Death are bros and got each other's backs! Even back when Dracula was Mathias and didn't have the ability to control demons, Death seemed sincerely loyal to him and fought Leon on his master's behalf. Naturally a lot of this is downplayed considering both Dracula and Death are murderous beings who want to bring pain and misery onto humanity... But it is still rather nice Dracula is able to find a sincere friend after his fall into darkness.
This friendship is perhaps best shown in Portrait of Ruin, where Death is fervently working against Brauner since the idea of someone else ruling over Castlevania is totally anathema to him. He is so determined to bring Dracula back as the true dark lord he even considers working with the heroes to achieve this. This comes to a peak in the final battle: where Dracula AND Death work together to try and take the heroes down! Also doubles as a Awesome moment.
Castlevania: Judgment also captures this in Death's story mode. While he remains malicious to the wide variety of heroes he meets, he takes Aeon's words completely seriously and does everything in his power to help him repair the timeline and ensure that Dracula remains his master. The closest thing he shows to antagonism is his insistence that he be the one to destroy those responsible, even if it means defeating Aeon first. "You would have done well to step aside." Compare this to how much he despises Saint Germain, the franchise's other time traveler.
This even extends to Dracula's reincarnation - in an officially approved novel that served as a sequel to Dawn of Sorrow, Death approached Soma and asked him to retake his title as Dark Lord, and when Soma refused... Death did nothing. He simply respected his wishes, and made no attempt to force the role onto him. He even stated beforehand that he had no desire to harm Soma. Crimson Stone or no Crimson Stone, Mathias or Dracula or Soma, Death truly valued him enough to let him pursue his own life.
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