In "Backwarder", after she mistakenly thinks Fu doesn't love her anymore and it is too late to reunite, she is akumatized by Hawk Moth into Backwarder, a time stealing villain who wants to recover lost time.
Marianne is a very petite woman. She has green eyes and grey hair that is tied in a bun.
As a civilian, Marianne wears a yellow buttoned collar shirt with a tan trench coat. She wears a yellow brooch with 愛 (love) on it, given to her by Fu on her shirt.
Backwarder has pale purple skin with yellow eyes and light lilac-colored lipstick. Her helmet is black and teardrop-shaped, with a yellow circle in the center of each side (not including the front or back), a large yellow key resembling that of a wind-up toy on top, and an upside down teardrop-shaped pale purple face mask with holes for her eyes and mouth, a small nose, two black dots beneath each eye hole, and a golden heart on the forehead, resembling a porcelain doll's face. Each time an object is touched with her sword, one of the cracks on the face of her helmet disappears. The main body of her costume is yellow and black, with a rounded shape resembling a clockwork doll. Her chest has a stylized clock face on the front where her akuma lies, with her brooch acting as the dial. On each of her shoulders, there is a yellow spherical pauldron. Her arms are mostly black, with accenting yellow "gloves" with scalloped ends. Her cane has also been transformed into a black sword with a golden tip resembling a clock hand, which she uses to activate her powers.
Marianne is a strongly nostalgic person as she desires to repeat the past and make up for her lost time with Wang Fu. She is confident and patient, being prepared to confess her feelings to Fu without hesitation, waiting years for him to be ready to come to her, while she continually came to the same spot in Paris.
Marianne is shown to be a very brave, selfless, and heroic person, as she was not afraid to stay in a Paris under siege during World War II and help fight back with the resistance, allowing Fu time to escape with the Miracle Box. Years later, she decided to hide herself this time so Hawk Moth couldn't use her to track Fu.
As Backwarder, she becomes quite aggressive and ruthless. She has no qualms using her powers on civilians and bystanders, despite the danger it might put them, as shown when she reversed a car and a woman with her stroller, causing the two to almost collide. Similar to how she was as Marianne, she desires to reverse her age in order to make up for her lost time with Wang Fu. However as Backwarder, she is willing to go to any lengths to accomplish this goal. She displays a large amount of confidence in her abilities, which led to her downfall, as she ignored Cat Noir once she had made him go backwards, deeming him no longer a threat and choosing to go after Ladybug instead, unaware this was Ladybug's plan from the beginning.
As a civilian
Marianne is strategic and clever, understanding that, using her power as Backwarder, she could force Ladybug to lead her back to Fu and the Miracle Box.
Wielding her clock hand sword, anything that is touched by the tip of Backwarder's sword begins to move and talk backwards in time, repeating their earlier actions. She uses this ability to grow stronger with every tap and redirect attacks. However, it seems that she cannot stop the things that she touches from going back in time, even if she didn't intend to use her power on them, as shown when Ladybug pushes her into a trash can to save Cat Noir, tripping her up and accidentally causing her to tap the trash can, causing all the trash to fly back out at her.
Backwarder has great speed, strength and agility, allowing her to leap great distances, as shown when she jumps to the top of a Ferris wheel with minimal effort.
Marianne met Fu years ago when he came to Paris and they started out as friends and soon their relationship turned into love. She was trusted with knowing his secret as the Guardian of the Miraculous. When the Nazis invaded Paris looking for them while trying to escape, Marianne encouraged Fu that they could fight back, wanting to take the Ladybug Miraculous. However, he refused and wanted to escape to England with her. Understanding her lover's responsibility, she respected his decision to leave while she fought. Before parting ways, she told him to speak his heart when he returned and was given his brooch being told he'd be back for it and her.
In "Backwarder", Marianne eagerly waited for Fu's arrival for years. However, upon receiving the wrong letter by mistake from Ladybug, she believed that Fu didn't love her anymore and her "futile" waiting to reunite with him left her vulnerable to akumatization. In her akumatized form, she desires to reverse her age in order to make up for her lost time with him.
After she was deamukatized, Marianne accepted Fu's apology of waiting too long to return and understood his fear and his isolation as the last guardian. She then warned him while during her akumatization Hawk Moth was one step closer to find him. Aware that her knowledge would put him and the world in danger, she understood that it was her turn to hide. The same as before when Fu wanted to attempt his feelings for her, she told him to wait until she got back.
Not knowing Marinette personally, Marianne seemed to be aware of her alter ego, knowing of Fu's secret. She was happy that Ladybug had a letter to give to her from Fu, however because of a letter mix up she was akumatized into Backwarder. After being deamukatized, she forgave Ladybug for the mishap and received the right letter.
As Backwarder, she was obsessed with striking the heroine with her powers in an attempt to find her lover. Due to that obsession she believed that the heroine a coward when she sacrificed her partner, unaware it was apart of her plan.
Before Season 3
Fu met Wang Fu years ago when he came to Paris and they started out as friends and soon their relationship turned into love. She was trusted with knowing Fu's secret as the Guardian of the Miraculous. She enjoyed a peaceful life with him until the Nazis invaded Paris looking for them while trying to escape, she encouraged him that they could fight back wanting to take the Ladybug Miraculous. However, Fu refused and wanted to escape to England, understanding her lover's responsibility she respected his decision to leave while she fought. Before parting ways, she told him to speak his heart when he returned and was given his brooch being told he'd be back for it and her.
In "Backwarder", Marianne eagerly waited for Fu's arrival however upon receiving the wrong letter by mistake from Ladybug. She had the idea that he didn't love her anymore and waited too long to reunite with him which left her vulnerable to akumatization by Hawk Moth. As the titular villain, she spent the whole time trying to reverse her age to make up for lost time, and upon seeing Ladybug she attempted to her powers to lead her to her lost love. However, thanks to Ladybug's complex plan she was deakumatized by the heroes after it Marianne given the proper letter by the heroine. Reuniting with Fu, she accepted his apology of waiting too long to return and warned him while during her akumatization Hawk Moth was one step closer to finding him. Aware that her knowledge would put him and the world in danger, Marianne understood that it was her turn to hide. The same as before when Fu wanted to attempt his feelings for her she told him to wait until she got back.
|Miraculous: Tales of Ladybug & Cat Noir Theme Song:||Absent|
|1. "Chameleon":||Absent||?. "Reflekdoll":||Absent|
|2. "Animaestro":||Absent||?. "Desperada":||Absent|
|3. "Bakerix":||Absent||?. "Startrain":||Absent|
|4. "Backwarder":||Appears||?. "Kwamibuster":||Absent|
|5. "Gamer 2.0":||Absent||?. "Feast":||Absent|
|6. "Weredad":||Absent||?. "Stormy Weather 2":||Absent|
|7. "Silencer":||Absent||?. "Timetagger":||Absent|
|8. "Oni-Chan":||Absent||?. "Ikari Gozen":||Absent|
|9. "Miraculer":||Absent||?. "Cat Blanc":||Unknown|
|10. "Oblivio":||Absent||?. "Félix":||Unknown|
|11. "Party Crasher":||Absent||?. "Ladybug":||Absent|
|12. "Christmaster":||Absent||25. "Heart Hunter":||Pictured|
|13. "The Puppeteer 2":||Absent||26. "Miracle Queen":||Appears|
- Her name is an homage to the grandmother of Fred Lenoir, a writer for the show.
- Her character is also a reference to his grandmother, who was a resistance member during a war.
- She was introduced in a synopsis that was released the show's Switzerland TV broadcaster, RTS Deux.
- Marianne is likely around the same age as Wang Fu, possibly making her the oldest known akumatized villain shown in the series.
- For reasons unknown, Marianne is aware of the Miraculouses, the Miracle Box, and Fu's duty as the Guardian.
- It's likely that Fu trusts her deeply, hence revealing his secrets.
- It is also possible that Marianne was a former Miraculous holder, as she asked for the Ladybug Miraculous in the past.
- Marianne may be one of the few beings to know Marinette is Ladybug, as she was the one to bring Master Fu to her when they are about to get on board in Startrain to get out of Paris.
- She is the second akumatized villain with time related powers, the first being Timebreaker.
- Coincidentally, both were indirectly made vulnerable to akumatization by Marinette while she tried to juggle three things at the same time: supporting her friends, fulfilling a task by an adult, and spending time with Adrien.