Based on their belief/illusion, they have prohibited marriage and romance between two races.
People act based on their recognition. The Rounds who recognised Triangles as an inferior race subsequently prohibited romance and marriage between the Rounds and the Triangles. It is because making a baby with an inferior race goes against the evolution of humans. |
N.B. This is not related to Jim Crow laws / Prohibition of Mixed Marriages Act / Immorality Act on this earth. |