Zhao Wu Xian, Zhao Yuan Man, Hou Zi Cheng and Lin Mei Xin are good friends who grew up together in the same orphanage in Yun Lin. In year 2009, Wu Xian, Yuan Man and Zi Cheng went to Taipei to pursue their dreams. They will be facing some challenges on the way, how will they overcome it?

Yuan Man thinks of her relationship with Wu Xian as siblings whereas Wu Xian does not. He wants to protect Yuan Man forever and would like her to be his partner. However this journey of love is not smooth, and may even reach bottleneck. However, their “Love” will definitely follow the “Circle” (Yuan/π) and back on its path again.