The students at Francois Dupont had been gathered in a group in front of Principal Damocles and a representative of the fire department, the fire alarm had been pulled and they found no fire. Principal Damocles was demanding that whoever pulled the alarm show themselves or else everyone will share the punishment.
Chloe Bourgeois of Ms Bustier's class was smirking to herself that her plan to disrupt the stupid cooking lesson by the father of the stupid Marinette Dupain-Cheng, she was in the clear and all she would have to do is stay silent and use her father to threaten the Principal to leave her out of the punishment. Her classmates should be thanking her for getting out of that stupid lesson and it would be a strike against Dupain-Cheng in her mind.
However she was taken aback when she felt her arm being caught by Ms Mendeleiev as she shouted "I wanted to wait and see if Ms Bourgeois here actually did see a fire before stating this but I personally saw Ms Bourgeois pulling the alarm herself. I gave her the benefit of the doubt that she was doing this in response to a fire but it seems that I expected far too much of it."
Chloe was stunned and saw everyone's glares go towards her and it was more insulting to hear the mutterings of the students saying they are not surprised it was her. Once she was brought to the Principal and firefighter, Chloe was furious when Damocles told her that she would be serving detention for the foreseeable future as well as be cleaning the school as punishment.
She then began phoning her father and threatened him to back off, Chloe handed it to Damocles direction with a cocky smirk thinking that it would make them back off to talk to her father. However Ms Mendeleiev was the one to take it and said "Mayor Bourgeois sir, I'm Ms Mendeleiev one of Chloe's teachers and your daughter decided that you should know that I caught her pulling a phony fire alarm and expects no punishment for her careless and dangerous actions."
Chloe shrank realising too late in hindsight that she didn't think this through too well.
It seems not even her father was willing to try and argue against a punishment for pulling the fire alarm and so Chloe had to serve the punishment with all school breaks spent cleaning the school while supervised by Ms Mendeleiev. She felt humiliation at the laughs and snide remarks from the students nearby. Even Ms Bustier was not happy with her, firmly telling her to keep quiet when she had a rant in front of the class because of her punishment. On top of that she had a month's grounding with Sabrina not being allowed over to do her homework.
She went to Adrien and he wasn't too happy to learn that she admitted that she didn't expect to get caught and would have been perfectly content to use her father to get out of punishment while everyone else served the punishment for her actions. After she was saying the class should be grateful that she was getting them out of that stupid class by Dupain-Cheng's father, she was shocked when Adrien told her that she had better start being nicer to everyone or else they couldn't be friends anymore.
She became an Akuma called Firefight but didn't last long against Ladybug and Chat Noir and spent the next month fuming about the self perceived injustices against her.