Boundary Foreigner (界境の異邦人, kaikyou no Ihoujin) is a Light Novel explaining the events that happens between Summon Night 4 & 5. It is the series biggest crossover to this day, assembling characters from the first game through the fourth. The choices are Magna, Rexx, Ray and , unexpectedly, all 4 main characters from Summon Night 1. The protagonist is a original character named Mochizuki Mikoto. It`s written by Miyakozuki Kei with illustrations and designs by Iizuka Takeshi (Kuroboshi Kouhaku) and Watanuki Nao.