Mahou Shoujo Oriko★Magica
Puella Magi Oriko★Magica
魔法少女おりこ★マギカ
Promotional material indicates the story will be set prior to the events of the anime, revolving around the initial interactions between Kyouko and Mami, along with a new Magical Girl named Oriko. Homura and Madoka will also be guest starring.
(Source: Puella Magi Wiki)