Form can reveal a habit
A character who records birthdays in a tide notebook tells you something about how family and work share attention. The notebook's format matters because it explains why those dates were seen regularly. In document-based fiction, an object's everyday purpose can carry characterization without a narrator announcing what the person felt. Read the practical use alongside the words rather than treating the format as decorative packaging.
A small fictional example
A worker uses an invoice to record an exchange of lessons for repairs. The printed money columns do not fit the actual arrangement, so a penciled note supplies the missing relationship. The mismatch between form and annotation becomes part of the story: two people give one another help while describing it in language that preserves their dignity.
Keep interpretation proportionate
A storytelling detail can suggest an emotional reading without proving every aspect of a character's inner life. Distinguish what is directly stated from what the arrangement invites you to consider. Somatry's invented definition, the science of what the dead leave in writing, gives this reading practice a thematic home. The appeal lies in following the traces carefully enough that a private habit becomes legible, while allowing the parts no record can settle to remain humanly incomplete.