There were several reasons why Lan Xiao wanted to open a shop in Jin Jing and cooperate with song Qiaoqiao.
First, her goal was to get into Jin Jing University. She was determined to get in.
Secondly, because Wen Muchu wanted to walk on that path in the future, he must stay in the Jin capital permanently.
Third, she didn't know anyone in Jin Jing. She wanted to use her relationship with song Qiaoqiao to open up a small entrance in Jin Jing. It would be much easier to do anything in the future.
Fourth, Jin capital was the capital of S Empire, the center of power and finance. If she wanted to catch up with Wen Muchu's footsteps, it was obviously impossible to develop in Ling city. Hence, she was indirectly paving the way for her to enter the Jin capital.
Five, it was naturally because she liked song Qiaoqiao. Because they hit it off and knew what she liked. She also wanted to do something big with her and change the song family's opinion of song Qiaoqiao.
