It's quite natural for Chen Zihuan to become hostile towards Huang Xiaolong!
At this birthday banquet, Chen Zihuan had no regard for others single men. He didn't think these worthless fellows could become his rivals in love. They were nothing compared to him!
However, with Shu Qinghan showing distinct feelings for Huang Xiaolong, the situation seemed to deviate a bit from the norm.
Regarding Shu Qinghan, Chen Zihuan considered her as a must-win, as he carried the mission of his family.
What about from Chen Zihuan's personal point of view?
He also had to win Shu Qinghan.