Shonen manga (and manga in general, along with lot of anime and live-action Japanese movies) uses exaggeration when depicting emotions, and Eiichiro Oda's One Piece is no exception. Here's a scene that I particularly liked from the fifth volume of the series, in which the character Usopp is saying goodbye to his friends as he goes off to join Luffy's pirate crew:
That final page is darn funny, with the emotion overpowering the characters to the point that they're weeping openly, tears and snot pouring down their faces like waterfalls, but it's not meant to be an embarrassing or humiliating moment. Instead, the emotion is real and heartfelt as they remember the good times they've had and wish each other well, and the exaggerated outpouring of feeling provides some catharsis rather than mockery of the characters. It's emotionally stirring and hilariously silly all at once. That's shonen manga in a nutshell: there's plenty of silliness, but it's still very sincere. I'll take that over ironic detachment any day.