There are various unofficial stories written by fans (e.g., The Golden Lily fan sequels or "Book 7" drafts on sites like Wattpad) that claim to be the seventh installment. These are not canon and are not written by Richelle Mead.
If you are looking for a "7th book" (или 7-я книга), you are likely encountering one of the following:
If you want to continue the story, I recommend starting the series, which begins with the book of the same name. To help you find what you need,