Yonegoro Nusumi

Yonegoro Nusumi is a victim Light kills in front of Raye Penber to prove to that he is really Kira. His death was not mentioned by L or any of the cops.

Cause of Death
At 3:00 PM on December 27, 2003, while wearing a hood to obscure his identity, Light holds Penber hostage in an underground section of the Shinjuku Station by killing Yonegoro Nusumi, an employee at a shop labeled "Cafeel" with a heart attack.

Nusumi had raped women but escaped a court conviction due to a lack of evidence, therefore Light feels justified in killing him. He is never seen or mentioned again.

Trivia
It is unknown wether or not Nusumi was actually a criminal. He may have been falslsley accused. Light may have killed him and just said he was a criminal. Or possibly he may have actually a criminal due to the fact he targets criminals at that point of the story. Light may have mistaken him for a criminal with the same name though none of these have been confirmed.