Pinnacle Chamber
From MHWiki
"The stairs that lead to the third and final floor of the Pagoda are behind a thick, opulent set of double doors and are extremely well guarded. The grand chamber of this floor is where the Masters of the Dojo reside, occasionally seen peering over the landscape they wish to enslave. Any hunter wishing to challenge these powerful mice will require an unstable and rare cheese."
The Master of the Dojo Mouse and Hapless Mouse lurk in this area.
You must have your Furoma map repaired by the Cartographer in the Bazaar before you can enter the Pinnacle Chamber.