Catalina was finding out about this Hannah girl. It seems to be one of the instances of Vitriolic teeth clenched teamwork, but there is more, such as her aggressive tendencies and what just might be affection. Then he realized he needs to withdraw as he heard the roaring inside his mind, then outside his mind.
Returning to looking at Desdemona he quickly turned away and excused "Oh, uh, nothing. Just... just wondering why I'm feeling so cold and chill air coming from your direction.",trying to put up a straight, innocent face as he spoke. Then he just tried to walk along and pretend nothing happened, hoping that dropping a comment on his power would let him be wary and not take any further actions, and making meaningless gestures with his hand to make him less nervous. At the same time one person went out of the dorm, Cat gave him a quick glance in his mind this time and it was lucky he did, because at that moment where they have eye contact Cat received so much distinct thoughts it almost make his head hurt. Cat gave him another look, this time more prepared, picking up thoughts a few at a time. Surprisingly, he found many, many people's mind within him, including his own and Vermilion's. Who else have suddenly developed superpowers, can I find this out with Kei's mind?