>>19990181basically its pokemon with youkais/japanese folklore monsters.
http://www.youtube.com/watch?v=kPWCJ6mZhM4the story goes that your some normal elementary kid in nipponland and you free this spirit that gives you a watch that allows you to see folklore monsters and you guys go on various hijinks together.
It has fun gameplay, some say it's better than pokemon because it's more engaging but I personally like both.
but the bad thing about youkai watch is that there's only a few out of the 200 youkais that have good designs/are shitmons. This usually leads to 'how the fuck did this game get so popular'
also Japanese humor