Toaru Majutsu no Index SS

This manga consists of two volumes, each containing short stories that expand on the main series. The first volume takes place between the thirteenth and fourteenth volumes of the main story and includes a prologue and epilogue, along with tales that explain the formation of Team GROUP. The second volume is set between the sixteenth and seventeenth volumes and features two separate encounters between the parents of Touma and Mikoto, two stories centered on two of Academy City's Level 5s, and additional lighthearted tales involving various characters.