Lin Xianer was intentionally trying to sow discord between Xia Wuchen and Xia Yi. Although she was being very subtle, Xia Yi could see through her.
After all, the Core Formation stage cultivator's divine sense could "see through the void," not to mention the Incarnation stage lord cultivator's. Incarnation stage lord cultivators just have to leave a wisp of divine sense and could see through everything.
Initially, Xia Yi was disdainful.
It was only because of the contamination of the devil's intent and his bad impression of Lin Xianer that Xia Yi decided to do it.
As for Xia Wuchen…
Not to mention the contamination of the devil's intent, this fellow originally had such a personality. Just after he was contaminated by the devil's intent, he began to become brainless and blindly arrogant.
There was no lack of people like this, but they also needed a huge backer to support them. Only then could they be unscrupulous and do whatever they wanted.