Persona 3: Owari no Kakera
ペルソナ3 オワリノカケラ
Owari no Kakera is an original story taking place one month prior to the beginning of the original game. It is told mainly from Akihiko Sanada's perspective beginning with him seeing a mysterious humanoid-shaped Shadow while exploring the Tartarus together with Mitsuru Kirijo.
(Source: Megami Tensei Wikia)