User blog comment:B214/Volume 23 discussion blog/@comment-177.177.104.45-20170618154943/@comment-86.159.78.224-20170618205157

Personally I always theorised they all (save for shin whose angel) were apart of the same peerage

Queen - kurenai

Bishop 1 - Robertina

Bishop 2 - Kurobora

Knight 1 - zen

Knight 2 - Ex

Rook 1 - Helmwige

Rook 2 - Shirayuki

Pawn - Airi x5

Pawn - Ernestein x3

And showing how they all fear him and being deemed a super devil would make him a king

King - Gasper