Nabeshin

ナベシン

"Nabeshin" is the well-known nickname of anime director Shinichi Watanabe. Watanabe is notorious for inserting himself into anime using his character, Nabeshin. He serves as the Deus Ex Machina in Excel Saga and is a main character in Puni Puni Poemi. Although he does not appear explicitly in Nerima Daikon Brothers, it is almost universally accepted that the "rental guy" character is one of Nabeshin's incarnations, as he, like all of Nabeshin's roles, is voiced by Brett Weaver in the English dub.
Additionally, he made a brief appearance in episode 24 of Yamato Nadeshiko Shichi Henge, and he also serves as the narrator in "The Road to Becoming a Lady" of the same series. Nabeshin appears in episode 32 of Hayate the Combat Butler, and has a 1-frame appearance as a mechanic in Eyeshield 21, episode 16. In SKET Dance, he had an appearance in episode 8 as a dub director.