Issac Devinsky is angry, and Xiao doesn't if it's because of her or something else on his mind, probably both. Princess Aurelia tagged along with Xiao back to her parents' carriage, and Gideon was the only one excited to meet her. Both of them shared the same enthusiasm about going to the Monastery, and they made it known.
Since they're in the presence of other people, Xiao can't talk to Princess Aurelia about what happened in the Abbot's office. Well, she just has to wait until there's another opportunity for both of them to be alone again to talk.