The TsumugiMark plugin introduces a vertical writing workspace aimed at authors working on novels, screenplays and Japanese text. It opens the current Markdown file in a dedicated vertical pane, keeping it visually separate from the standard editor while staying fully in sync. Edits flow both ways. Type in either view and the content updates immediately. The plugin supports ruby characters for furigana using a custom inline notation, making it practical for complex kanji heavy writing. A built in character counter tracks total length and selection size directly from the status bar, which helps with manuscript limits and pacing. Visual preferences are flexible, with controls for font family, size, spacing, and how characters are counted.