Ray Penbar was one of the 12 FBI agents attached to the Kira case, and the most predominantly featured of the agents - as he observed Yagami Light.
He was also engaged to another minor character, Naomi.
Raye Penber (レイ・ペンバー) is an investigator from the FBI, sent to Japan with eleven other agents to aid in tracking down Kira early in the story. Described by How to Read It as a "talented" agent, Raye is assigned to investigate the Yagami family for any suspicious behavior. He has a fiancée, Misora, whom he tells not involve herself in the investigation for her own safety. Light manages to track him down and use him "as a pawn" to kill the other eleven members of his team (he unknowingly used a page of Light's notebook to kill them, but didn't use it to kill maliciously). Light kills Raye soon after. Raye is voiced by Hideo Ishikawa in the Japanese anime and Michael Adamthwaite in the English dub. In the films, he is known as Raye Iwamatsu (レイ・イワマツand he is played by Shigeki Hosokawa. In the first film he is a counter-terrorism agent headquartered in Dallas, Texas.
Ohba said that at the beginning he thought of the idea of the FBI going after Light, and so he created Raye to fill the plot point.
Raye's role in the overall plot is fairly small and he is fairly normal character-wise. However, he is important in the narrative. All of Light's previous murders have been unpleasant-looking, criminal or ill-behaved people that the reader knows very little about. Furthermore, the murders have been told entirely from Light's perspective. Raye, however is a decent, dutiful and innocent person and his fatal encounter with Light is mostly told from Raye's perspective. This encounter is described in detail allowing the reader to empathize with Raye's horror when he is forced to betray his collegues to protect his fiancee. With the murder of Raye Pember Light loses both much of his ethics and probably much of the reader's sympathy.
Obata said that as Raye was of mixed American and Japanese descent, Obata "struggled over his design" and tried to make Penber look more non-Japanese. Obata said that he wishes that he could have "drawn him a bit better." Hosokawa said that when he portrayed Raye he built Raye's "strength, tenderness and the feeling of mortification."