Yū Sasuga is a Japanese manga author born in 1988 in Fujisawa City, Kanagawa Prefecture. After graduating from Shonan High School in 2007, he attended Saitama University, where he studied cultural anthropology in the Faculty of Liberal Arts, graduating in 2013. Sasuga has cited reading the manga Century Legend by Shimabukuro Mitsutoshi in elementary school as an early inspiration to become a manga artist, though he initially pursued other interests, including serving as captain of his high school rugby team.

Sasuga began his career as an assistant to the manga artist Tachibana Kenichi. An editor recognized his writing abilities and encouraged him to work as an original creator rather than an artist, noting the strength of his narrative concepts. This advice led to his professional debut. In 2011, with the launch of Miracle Jump magazine, Sasuga began publishing his first and most prominent work, Terra Formars, with Tachibana Kenichi providing the illustrations. The series was initially serialized in Miracle Jump from its first issue through the sixth issue, with those chapters collected in the first volume. The series later moved to Weekly Young Jump, where it continued as a regular serial.

As the original creator of Terra Formars, Sasuga is credited with the story and conceptual framework, while Tachibana handles the artwork. The manga is a science fiction action horror story set in a future where overpopulation on Earth drives humanity to terraform Mars. The terraforming process involves releasing algae and cockroaches to alter the Martian environment. When a crewed mission eventually arrives, the explorers discover that the cockroaches have evolved into large, aggressive humanoid creatures with immense physical strength. Subsequent human expeditions send genetically modified soldiers who have undergone the Bugs Procedure, receiving insect DNA enhancements to fight the Terraformars. The series explores themes of evolution, survival, and the unintended consequences of human intervention in nature.

The Terra Formars manga has been adapted into multiple anime productions. In 2014, an original video animation titled Terra Formars: Bugs 2 was released. Later that same year, the first anime television series, simply titled Terra Formars, premiered. In 2016, two additional anime works were released: Terra Formars: Revenge, a second television series, and Terra Formars: Aratanaru Kibou, also known as Terra Formars: A New Hope. Also in 2016, a live-action film adaptation of Terra Formars was released, directed by Miike Takashi. Sasuga is credited as the original story author for all of these adaptations. Several spin-off manga series have also been produced, including Terra Formars Gaiden: Keiji Onizuka, Terra Formars: Rain Hard, and Terra Formars: Asimov.

Sasuga operates specifically as a manga original creator, providing the story and narrative structure while collaborating with illustrators. He has not worked as a voice actor. Beyond the extensive Terra Formars franchise, his published works include several short stories set in the same universe, including Terra Formars 1 published in Weekly Young Jump in 2011, and the two-part Great Devotion series in 2013. He has also contributed design work for other media, including album cover art for the band Seikima-II.