The October issue of Bessatsu Friend revealed that the manga Ran the Peerless Beauty ( Takane no Ran-san ) will end in four chapters, including the chapter published last Saturday.
Ran the Peerless Beauty was launched in July 2017, and Kodansha published the 9th volume of the manga last Friday.
And that same 9th volume then revealed that the 10th and final volume of the manga will be released in January.
Source: ANN