This monograph is a study in the field of grammatology, applying two key theoretical frameworks—functional structure and formal (morphological) structure—to examine invented Nôm characters of Vietnam through a representative Nôm text from the late seventeenth century: the vernacular gloss of Truyền kỳ Mạn lục. The monograph is divided into four chapters: Chapter One introduces the Nôm script and the text Tân biên Truyền kỳ Mạn lục; Chapter Two presents the theoretical foundations of grammatology and an overview of invented Nôm characters in the vernacular gloss of Truyền kỳ Mạn lục; Chapters Three and Four respectively approach the study from the perspectives of functional structure and formal structure, analyzing the invented Nôm characters within this text. In addition, the monograph concludes with nine appendices, which provide supplementary materials to help readers better understand its contents.