Hiroki Iwata is a Japanese light novel author known for creating the original story that was adapted into the anime series Venus to Mamoru. Born on December 13, 1983, in Hiroshima Prefecture, Japan, he began his professional writing career in July 2002 with the publication of his debut work, Haiiro no Iris, under the Dengeki Bunko imprint from MediaWorks.

Iwata is best recognized as the original creator of the light novel series Mamoru-kun ni Megami no Shukufuku o!, which was published in 16 volumes from September 2003 to March 2009. The series, illustrated by Toshiyuki Satō, centers on a romantic comedy set in a school for individuals who wield a supernatural power known as Beatrice. It was this work that served as the source material for the 24-episode anime television series Venus to Mamoru. The adaptation, produced by the studio Zexcs, aired on the WOWOW network from October 2006 to March 2007, with Mari Okada handling the series composition.

Beyond this notable work, his bibliography as a light novel author is extensive. He contributed a separate series titled Tsuki no Tate in 2006. Between 2010 and 2013, he wrote the light novel series Hana x Hana, which spanned eight volumes and was later adapted into a manga. His other published works include the light novel series Hangyaku no Dreadnought from 2014 to 2015, Tenohira no Koi to Sekai no Ou no Musume-tachi from 2016 to 2017, and the more recent series Game of Vampire in 2022. Throughout his career, he has consistently worked under the Dengeki Bunko label, with many of his series receiving multiple volumes, indicating a sustained career within the light novel industry.