Here is a brief summary of what Konjiki no Gash Bell is about.

When he holds a mysterious red book and chants a spell, a lightning attack comes forth. When this strange boy Gash arrives at his house, the life of lazy middle-schooler Kiyomaro Takamine is thrown into chaos!! Gradually, Gash's true identity and abilities are revealed! Children from the demon world come and attack one after another!! What is the destiny of Kiyomaro, who has decided to fight alongside Gash.!? New super-intense battle action!!

I got this summary from www.animenfo.com

Very nice show to watch all should watch.

Anime-destiny@rizon.net is currently subbing it. They are doing both Thousand mamono battle and Fauudo battle arc.

Currently ep 68 is the 千円前の魔物 battle. While ep 101 is ファウド battle.

Also there's a great community at LJ for Gash Bell.
Link: http://community.livejournal.com/konjiki/