In male-dominated medieval Japan, the ladies of the court kept journal-style books under their bed pillows, used as an outlet to express themselves. These pillow books contained court gossip, as well as the ladies' innermost secrets, hopes and dreams.
In lieu of crying into their pillows, they slipped their identities under them. Writing what they really felt was at least one effective way these women could keep a handle on who they were in this "be-seen-and-not-be-heard" society.[pillow books]