And the second layer must be understood from Sakuragi Yuri's description.
Think about it, how would someone like Alvira use terms like "Vice President" or "stepsister" to refer to Sakuragi Hitomi and Ye Shiyu.
If she were to speak, she would certainly say "the young lady of the Sakuragi Family" or "the heiress of Ye International."
So, Sakuragi Yuri subjectively chose to say it this way.
And whether it's "Vice President" or "stepsister," both terms describe their relationship with Yan Huan.
It's Sakuragi Yuri's way of reminding Yan Huan of Alvira's motives.
She introduced two women who might be related to him to break up his world with Spencer...
The reason Yan Huan can think of right now...
One is to focus on tutoring work and interrupt the development of their relationship.
The second is to remind himself and Spencer that there are other potential women around him.