Seiji Okuda, born on April 18, 1943, is a Japanese animation director, animator, and storyboard artist known for a career spanning from the mid-1960s into the 2020s. He debuted in the industry in 1965 working on the anime Ironman No. 28. Over his extensive career, he became renowned for his exceptional speed as a storyboard artist, earning a reputation for drawing over a thousand storyboards and being nicknamed the Demon of Continuity.

As an original creator, Okuda is best known for developing the Dream Hunter Rem franchise. He served as the original creator, general director, and screenplay writer for the OVA series Dream Hunter Rem, which was released from 1985 to 1992. The series, which blends horror, action, and supernatural elements, initially began with an adult-oriented release before being re-edited into a general version due to its unexpected popularity. He continued to work on the franchise with the subsequent OVAs New Dream Hunter Rem: Massacre in the Phantasmic Labyrinth and New Dream Hunter Rem: The Knights Around Her Bed, both released in the early 1990s.

Beyond the Dream Hunter series, Okuda’s credits as an original creator and director include several other OVAs from the mid-1980s. He was the original creator, executive director, and screenwriter for Twinkle Heart: Gingakei made Todokanai in 1986 and also for Paradox Dimensional Romanesque Samy - missing'99 in the same year. His directorial work also extends to television series such as Super Beast Machine God Dancouga (1985) and Mitsuteru Yokoyama's Romance of the Three Kingdoms (1991).

Okuda’s artistic identity is closely tied to his work as a storyboard artist. His skill in this area was highly regarded by prominent directors like Isao Takahata and Yoshiyuki Tomino, with his storyboards noted for their dramatic expression and action sequences. However, his distinctive style of drawing characters with rounded facial features is a noted characteristic that has been met with mixed responses. In addition to his directorial and storyboard work, he also used the pen name Mitsuwa Yamatani for some of his projects. His industry significance is underscored by his prolific output and his contributions to foundational anime, having worked on classics like Heidi, Girl of the Alps and Dog of Flanders early in his career.