Heartwarming / The Wonderful World of Puss 'n Boots

• Pero and Pierre's friendship. The song they sing together as they travel the world is just as heartwarming.
  I've got you, and you've got me, and just between the two of us
  I'm for you, and you're for me, and that's between the two of us
  So together, we can weather, anything that comes along
  We can face the world, and know, that nothing can go wrong

• Pero in general, compared to his literary counterpart. He is much more kind and gentleman-like to (close to) everyone around him. And all the schemes he plots were to help others out, rather than himself. He does still perform unconventional means to achieve his end result, but it's the thought that counts, to him.

• The blossoming relationship between Pierre and Princess Rosa. Even after the former confesses to the latter that he was just a miller's boy, and not a prince, Rosa says that she didn't care, and said that she loved him for who he really is. And at the end, after Lucifer is defeated, the two finally get married.