Ryō Takagi is a Japanese manga artist known for creating works in the boys' love genre, which focuses on romance between male characters. The creator is noted to be female, with a birthday of September 6th and blood type B. Her professional debut was with the comic Okome-chan in 2001. She has also been known to work under the pseudonym Hazuki Ryōka.

Takagi is best recognized as the original creator of Kirepapa, a yaoi manga series that blends romance and comedy. The series was first published in Japan in 2003 by Core Magazine and was completed in four volumes released up to 2009. The story centers on Chisato Takatsukasa, an overprotective novelist who tries to scare away his son's friends, only to find that one of them, Shunsuke, is actually interested in him.

In 2008, Kirepapa was adapted into a two-part original video animation. The OVA was directed by Ai Guchi, written by Kai Koishikawa, and produced by the studio AniK. For this adaptation, Takagi is officially credited as the original creator. The OVA's character designs were handled by Shūhei Tanaka, and the cast included voice actors such as Hikaru Midorikawa as Chisato and Takahiro Sakurai as Shunsuke.

Beyond Kirepapa, Takagi has a substantial bibliography of manga titles. Her other works include Double Essence, Brandoll, Get the Moon, Love Guardians, The Devil Within, and the Game series which features titles like Prince's Game, Pirate's Game, Butler's Game, and Thief's Game. Many of these works have been translated and published internationally, including German-language editions released by Egmont Manga. A selection of her other known works includes Kuro x koi, Zero Distance, Love Observation, Café Men!, and Wonderland Love. Her artistic output places her as a consistent contributor to the boys' love genre, with her career spanning from the early 2000s into the late 2010s.