Alya Césaire

Alya Césaire is Marinette's best friend, and a student in Miss Bustier's class at Collège Françoise Dupont. She is also the sole admin of the Ladyblog and head of the school blog. In "Lady Wifi", after Alya gets suspended from school because of Chloé, she is akumatized by Hawk Moth and becomes Lady Wifi, a supervillain whose powers come from her smartphone and its Wi-Fi signal.

Bio
Alya is rather energetic, passionate, and funny, confident, yet down to earth. Alya's foresight have come in handy many times. After Marinette thinks she accidentally lost a video of Ladybug on Alya's cellphone, she explains that she had already posted the video on her blog, mindful that something might go wrong when she showed her clumsy friend the video. When it comes to anything involving Ladybug and Cat Noir, she easily becomes very excited and basically has a single goal of updating her blog as soon as possible, such as when she is kidnapped by the Pharaoh to be a sacrifice yet still records herself and live streams the video on her blog. Sometimes, she goes too far, such as spying on Chloé's locker, which results in her getting punished by Mr. Damocles. Alya doesn't like being undermined or doubted by others, especially when it comes to her work. If someone points out something wrong to her, she is to stubborn to admit they are right. Though her research is generally right when she takes her time, Alya tends to jump to conclusions, like quickly suspecting Chloé of being Ladybug after seeing the girl with her own Ladybug suit and toy yo-yo and mistaking them for the real ones. She also has a habit of never checking her sources or doing ethical investigating of her blog posts, while demanding others to provide proof for their claims, even though she doesn't do that herself often.

Alya is extremely loyal, supportive, helpful, and sometimes pushy, such as when she goes out of her way to encourage and (sometimes literally) push Marinette into spending time with Adrien. She is also very stubborn when it comes to doing things her way, such as the photo shoot of Marinette's fashion line. Another side to her is that she can be a bit demanding at times just as keeping Nino in line about revealing Marinette's crush on Adrien. Alya has a dramatic side to her personality, such as when she pretends to be a unicorn with Manon and later makes an excuse to Adrien's photographer, who asks her to be a support model for Adrien, so Marinette can do the modeling instead. Having to babysit her younger siblings at home, she is great with kids, though sometimes she pushes her responsibility of watching them on Marinette so she can go on dates with Nino.

As described by Cat Noir in "The Pharaoh", Alya is a "brave chick," unafraid to get close to villains in her pursuit of the truth, tending to forget her safety at times and needing rescue by the very superheroes she is filming. As Ladybug, Marinette calls Alya bossy, feisty, and bold. Her bravery and determination has helped both civilians and superhéroes, such as when she makes a plan with her classmates to save Marinette and sacrifices herself in the process or rides a bike to distract the Gigantita from harming Ladybug, showing a more compassionate side towards her beloved ones in danger and great skills in leadership.

Alya holds great admiration and respect for the two superheroes, especially Ladybug, wishing to know anything and everything about her. Much more, she wildly dreams of knowing Ladybug's identity, not once thinking about the consequences of posting the information on her blog, as Marinette pointed out to her in several episodes. However, she would respect her desire to keep it secret. Alya wishes to work alongside her, her dream coming true when the superheroine chooses her to wield the Fox Miraculous and asks her for her help in defeating Sapotis. She greatly values the trust Ladybug has in her, making her someone of her word above her burning desire to continue helping her teammates and thus giving her Miraculous back.

As Rena Rouge, Alya retains most of her personality traits such as her undying loyalty, trustworthiness, and curiosity. She is supportive of her allies, whom she gets very excited about working with, causing her to be a bit of a scatterbrain. A fast learner, she takes quickly to her abilities.

As Lady Wifi, her desire for answers increases considerably. Despising Ladybug's secrecy, she will stop at nothing to find out her secret identity, even if it means exposing a horrible person underneath, such as when she believes that Chloé is Ladybug. Her speediness to update onlookers remains the same, but her methods for finding info become sneakier and harsher.

As Oblivio, she wants nothing more than to erase the memories of everyone in Paris.

Physical appearance
Alya is a Martiniquan Creole-French girl with the height of 5'5" and a curvaceous body. She has heart-shaped lips, hazel eyes, and a mole above her forehead. Her hair is wavy and reddish-brown ombre, growing slightly past her shoulders and having light copper-red tips.

Civilian attire
She wears black horn-rimmed glasses, with a white spot on each side. Her outfit consists of a white tank top underneath a short-sleeved plaid shirt with white, orange, and purple stripes; light blue jeans, and white sneakers with black tops. She wears a light red-colored lipstick.

As Rena Rouge
When transformed, Rena Rouge's hair turns longer becomes a three-tone ombré, having the roots turn dark red/red-orange, mixing to orange with the tips being white, and she wears her hair back into a high ponytail with an orange headband. Her body is slimmer than her civilian form. The top layer of Rena Rouge's suit, akin to an overcoat, is orange with a white front, a black swan-necked collar, and black arms and gloves up to the middle of her upper arms. The overcoat layer attaches down the vertical front center with a zipper, and the Fox Miraculous becomes the zipper. The overcoat also has a long fox tail-like coattail that ends a bit below her knees at a sharp white tip. The bottom layer of her suit is orange with a white center on the front of the body and black legs starting at a point in the middle of her upper legs. She also wears black boots with orange soles and black fox pawprint markings. Rena Rouge wears an orange mask with a white bottom half and a black mark above each eye. Two orange fox ears with white insides, black tips, and black edges are attached to the top of her head. She attaches her flute diagonally on her back when it's not being used.

As Lady Wifi
Lady Wifi has a black butterfly-shaped mask on her face, and her eyes are dark magenta. She wears a black suit, her lower arms, and legs white with three stripes that are white above each. On her chest is a glowing hot pink Wi-Fi symbol, and a thin white line goes around her waist, with the line creating a semicircle above a short vertical white line in the front, resembling a power button.

As Rena Rage
In "Mayura" Rena Rage has the same appearance as her superhero counterpart except for being red all over, owing to her having been taken over by a scarlet akuma. Her appearance resulting from a regular akuma is unknown.

As Oblivio
Oblivio is a purple silhouette that has a laser cannon in its left hand and wears a gray glove on its right hand.

Trivia

 * Alya will meet Tino Tonitini, Bloom, Ash Ketchum, Littlefoot, SpongeBob SquarePants, and their friends in Tino's Adventures of Miraculous: Tales of Ladybug & Cat Noir.