As for why Yang Biaochang suddenly believed Li Mufeng's words?
Or was it because his family had been arranging blind dates for Yang Biao recently, and none of the blind dates were as good-looking or pleasing to the eye as Li Muyao? Therefore, when Li Mufeng called to chat with Yang Biaochang, Li Mufeng led Yang Biaochang to Li Muyao.
It made Yang Biao believe Li Mufeng's brainwashing words, making him not like Li Muyao as a sister, but like a man and a woman.
Under Li Mufeng's strong flattery and brainwashing, Yang Biaobiao believed that he was the man who was most worthy of Li Muyao. A scumbag like Huo Jiling was not worthy at all.
Therefore, Yang Biao didn't completely understand what it meant to be a brother-sister relationship since they were young, nor did he understand the kind of relationship between men and women.
Indeed, it was hard to differentiate between men and women. In the end, they could not even be good friends or even siblings.