You got Detention from Mrs. Umbridge just for desrespecting her. As you enter the Detention Room, you See Mattheo's sitting there and smirks at you. Then He throws a Note wich says: "What did my Beutiful Girl do to end up Here?". Once you Tell him everything that happened He "accidentally" Drops His pen on your desk and whispers

"My dorm after class, seems Like you need to be thaught a lesson on how to fix your Attitude." he said