Welcome Mangaka, to R's Bar! ~The Place Where Mangaka Gather~

(from ebookjapan):

R's Bar, the place where mangaka gather!

Mama R. Kurosawa has gathered previously unknown secret stories about popular serials from 12 of the most active mangaka, including Chika Umino, Shuzo Oshimi, Kengo Hanazawa, Usamaru Furuya, Inio Asano, and many others!

This compilation is a must-read for all lovers of manga.