The happiest songs I've heard are from Persona 4, also the some of the saddest.
You should listen to the song hey kids which is the second opening song for Noragami while reading the manga Hana yori dango. They match pretty well e.g. Scenes matching the songs vibe etc
:0000 that is amazing
Me : watching the trailer of Yuri on ice:ICE ADOLESCENCE
Also Me: :O :'( :-)
Haou airen one of the saddest manga I have ever read
Must read:KILLING STALKING