|Series:||AKB48 Murder Mystery|
|First Appearance:||Testimony File|
|Last Appearance:||Testimony File|
|Number of Episode|
|1 (Testimony File)|
Kobayashi Marina (小林茉里奈?), nicknamed Marinchan (まりんちゃん?), is part of AKB48's Research Students (Team Kenkyuusei). She is one of the primary characters in AKB48 Murder Mystery series. She was based on and was portrayed by Kobayashi Marina.
All 89 members of AKB48 went to a duplex island owned by one of Akimoto Yasushi's friends for a CM Shoot. After their first day shoot was over, they went to their designated resthouse on the other island. It was assumed that she heard that Kato Rena was missing and was shocked to learn that the scream they heard was from Sashiko finding the girl's lifeless body in the dining hall.