Multicultural conviviality, borderless society, and flat society were once buzzwords. The more we understand the high hurdles involved in realizing these ideals, and the gap between the ideal and the reality, the more it seems overwhelming due to the numerous challenges. However, within our daily lives, there are practical examples where people seemingly divided by borders manage to overcome difficulties through ingenuity and negotiation, opening up new horizons.  Alternatively, there are individuals who, despite appearing confined by various borders, create vibrant everyday lives when explored. From the perspective of the humanities, in this research group, we aim to study the dynamics of communication and the impact of spaces created through the intertwining of people, using keywords such as cross-border, mobility, boundary, and negotiation, through examples from various regions of the world.