A genius computer programmer. She looks down on Taketo the most out of all the students, often calling him a porno writer. With her skills she is able to hack into government satellites and computers. Ran's hacking abilities are so superior that she can hack anything. Ran is shown to be only interested in girls and hates Taketo.

Later in the show Taketo saves her against Botan, and she starts to see him as a friend. Eventually being one of his closest friends by the end of the series, but still violent towards him off and on.