beta
Reposting my explanation on the Story, in case you are confused:
https://www.mangago.zone/home/mangatopic/15229274/
Chapter 24:
https://www.mangago.zone/home/mangatopic/15230469/
Anyway there is a mistake in it, the evil stepmom is the aunt of Jitae (based on around ch 14), and the fight is between her and Jitae to decide who will inherit the company. This lady is tge stepmom of Jian, as Jian was born from a mistress.