The custom unit was designed by City Joinery around the antique Japanese tansu.
Was Houzz-User dazu sagen:
this bookcase shows Japanese influence - which was appropriate and intentional as related to our tansu. Designed, with some input from me, by Jonah Zuckerman of Citi Joinery. Google his work if you have time - he's a tremendous designer. He also designed and produced the bed in this bedroom - to me it looks "japanese". Also his - the dining table (the same project).