Hiroshi Sakurazaka is a Japanese author best known for his work in the light novel genre, whose stories have served as the foundation for several major anime and manga adaptations. Born in Tokyo in 1970, Sakurazaka originally worked in the information technology industry before pursuing a career as a writer. His background in IT has significantly influenced his writing, particularly his interest in computer culture and programming languages such as Perl. He made his literary debut in 2002 when he entered the second Super Dash Novel Rookie of the Year Award, and his first novel was published in December 2003.

Sakurazaka is credited as the original creator behind the light novel series Modern Magic Made Simple, known in Japanese as Yoku Wakaru Gendai Mahō. The series began publication in 2003 and was subsequently adapted into multiple formats. A manga version, illustrated by Miki Miyashita, was serialized in Jump Square from August 2008 to September 2009 and compiled into two volumes. A twelve-episode anime television series adaptation produced by studio Nomad aired from July to September 2009, with an additional OVA episode released prior to the television broadcast.

His most internationally recognized work is the 2004 science fiction novel All You Need Is Kill, published by Shueisha's Super Dash Bunko imprint with illustrations by yoshitoshi ABe. The novel received high praise from other authors in Japan and earned a Seiun Award nomination. The story follows a soldier trapped in a time loop on a battlefield against alien invaders known as Mimics. This novel formed the basis for the 2014 Hollywood film Edge of Tomorrow, directed by Doug Liman and starring Tom Cruise and Emily Blunt. The manga adaptation of All You Need Is Kill was illustrated by Takeshi Obata, the artist known for Death Note, and published by Viz Media in 2014. This manga version was released in English as a single volume in the Shonen Jump Advanced imprint.

Beyond these major works, Sakurazaka has written other novels including Slum Online, published in English by Haikasoru in 2010, and Characters, co-written with cultural critic Hiroki Azuma. In 2004, he won the 16th SF Magazine Reader's Award for his short story "Saitama Chainsaw Massacre." In 2010, he co-founded an experimental digital magazine called AiR with Junji Hotta.

Recurring themes in Sakurazaka's work often blend science fiction concepts with contemporary technology and gaming culture. All You Need Is Kill draws heavily on video game mechanics, particularly the concept of respawning after death and learning enemy patterns through repeated attempts, which reflects his stated passion for gaming. Modern Magic Made Simple similarly incorporates computer programming terminology into its magic system, with terms like Garbage Collector and Ghostscript appearing as volume titles, bridging the gap between fantasy and information technology. His protagonists are typically ordinary individuals placed in extraordinary circumstances, and his writing style is noted for its accessible prose and fast pacing.

Sakurazaka's industry significance lies in his ability to create light novels that transcend the typical boundaries of the genre, achieving crossover success into mainstream science fiction and Hollywood film adaptation. All You Need Is Kill became the launch title for Haikasoru, an imprint dedicated to publishing contemporary Japanese science fiction for English-speaking audiences. His work has been praised by authors such as John Scalzi, who described All You Need Is Kill as a novel that reads fast and delivers impactful action. While he continues to write both light novels and adult science fiction, his legacy as an original creator remains most visible through the multiple anime, manga, and film adaptations that his stories have inspired.