The domain realm master who Ling Lan stopped was the strongest among the three domain realm masters that were hiding in the manor. Ling Lan had detected his force of presence and concluded that he was only half a step away from becoming a titled domain realm formidable warrior. Hence, she decided to stop this person herself as no one other than her could match-up to him. Plus, Ling Lan had already made the decision to eliminate everyone here, so she would, of course, not allow anyone to escape.
The domain realm master frowned when he saw Ling Lan appearing in front of him. At first, he thought that Ling Lan would stop the weaker domain realm master, so he was slightly furious that Ling Lan chose him. Did his opponent think that he was afraid? He only chose to escape because he didn't want the manor to suffer more damages and was also going to look for reinforcements.