Vaelki
During a akuma attack, Marionette's father is badly injured because of Ladybug, and has to be taken to the hospital. The doctors don't know if he will live, and Marionette blames herself. She knows how dangerous these emotions are, being easy prey for a akuma, and tries to keep them in check. But when Chloe decides to taunt her, she is pushed overboard and is akumatized, and it's up to Chat Noir to free her from it. But he can't cleanse the akuma and Ladybug knows him and how he fights. How can he battle someone he loves and who knows him so well? And more importantly, how can he free her from Hawkmoth's grasp?
Note: Written in 2016. This story is old and discontinued. Also my writing here is really bad ew.
(Disclaimer: I do not own Miraculous Ladybug or any or the characters, the story alone is mine.) (Cover art is not mine)