Why do the Spy x Family covers show designer chairs?
Endo seats each cover character on a real, named designer chair, chosen, in his stated reasoning, to match that character's personality, with the character's secrets hidden under or behind it. Volume 10 deliberately breaks the pattern.
The documented pattern
Matched to personality
The rest of the shelf
Volumes 5 to 9The identifications continue, cross-checked across the series wiki's volume pages, which cite Endo's own statements, a design press roundup, and the chapter list: Vol. 5, Yuri Briar, the Barcelona Chair by Mies van der Rohe and Lilly Reich, picked, Endo admits, because he could not think of one that fit and went with the classic. Vol. 6, Fiona Frost, the Heart Cone Chair by Verner Panton, a design first drafted for Yor. Vol. 7, Damian Desmond, the Willow Chair by Charles Rennie Mackintosh, made for a business supervisor, matching a boy desperate to appear grand. Vol. 8, Franky Franklin, the Eames Lounge Chair and Ottoman. Vol. 9, Becky Blackbell, the Coconut Chair by George Nelson. A common swap to avoid: Volume 1 is not the Barcelona chair. That is Volume 5.
What is under the chair
The pattern readers foundWhat is hidden under or behind each chair is what the character hides: Loid's spy tools, Yor's blood, Yuri's secret police kit, Fiona's unsent love letters, Damian's suppressed toys. Anya and Bond, who hide nothing, have nothing under theirs. The items are documented cover details; the reading of them as the characters' secrets is the fandom's interpretation, labelled as such. Volume 10 breaks the motif: Endo dropped the designer chair to make the cover fit that volume's story, so 'every cover' is not quite true. And an honest limit on the why: the per-character matching is documented in Endo's statements. A founding 'I love furniture design' origin story is not in the sources opened for this page, so this page does not invent one.