This essay spotlights the experiences of otherness and marginalization of ethnic roots migrants in today's South Korean society. It argues that their sense of liminality and rejection by both societies (diasporic and ethnic home), when examined through the concept of mestizaje, reflects their unique capacity to be bridge builders between the dominant majority and the excluded minority, including themselves. Also, using intercultural theology as a frame of theological reference to interpret the presence of roots migrants as both insiders and outsiders, the essay unmasks the overall fear of otherness and pride in homogeneity in Korean society that seldom problematizes the alienation of those labelled as the "others." Finally, it discusses the importance of a genuine theological interpretation concerning the issue, so that it can construct spaces for an alternative understanding of identity and otherness that does not lead to exclusion but to embrace.