Weiss knew that for Elise, kissing her dear mistress was a very surefire way to calm her down, make her mood better and relax her mind and emotions. And that was exactly what happened with her after she was done kissing Weiss.
Seeing that Elise was calm now, Weiss asked her about what had happened. Then after taking a long breath, she started to explain the situation to Weiss.
And the situation was almost exactly what Weiss had thought of. These two nobles were blackmailing her using something that Elise really cared about.
As for what exactly was the source of this blackmail, it was actually a family member of hers. This family member was extremely close to her and Elise also cared about this person a lot.
The person in question was her father's younger sister, so it was her aunt. In the Triston family, she was a rare intellectual who liked books more than weapons. And Elise was very very close to her.
