The concept of 别扭 (bièniu) is deeply intertwined with the Chinese cultural value of 和谐 (héxié) - harmony. In Chinese culture, great importance is placed on maintaining smooth social interactions, group cohesion, and a general atmosphere of comfort and ease. Anything that disrupts this flow is undesirable. 别扭 is the word that describes that disruption. It's the anti-harmony.
This makes 别扭 a crucial term for understanding the emotional landscape of Chinese social norms. When someone says a situation is 别扭, they are signaling a breach in the desired state of harmony.
别扭 (bièniu) is a common, informal word used in many contexts.