From Mahou no Ribon:

Himeko is an energetic, cheerful tomboy who has a catch-phrase to cheer herself up ("Ike, Ike, go, go, JUMP!"). Yet she somehow lacks the courage to tell the older boy at school that she has a crush on him. Perhaps she's just not feminine enough? Magically and mysteriously, Hime-chan meets someone who is the mirror image of herself, but she's a princess! Erika, from the Magic World, has come to give Hime-chan a present that she's invented, a magical ribbon, that will allow her to turn into the image of anyone else for one hour. This ought to help solve Hime-chan's problem, shouldn't it?

Would you like an older man dressed in suits? She was never this popular before university but before she knew it, Risa was way out of everyone’s league. The one who saves her from this cruel fate is a handsome man who can rock his suits, Fukami-san. What will he offer Risa, who is a beginner at love…!?

Regina, whose father was the emperor that got assassinated, became the regent on behalf of her younger brother.

While facing plenty of hardships, news about the depletion of national funds due to her maniac younger brother's behavior, as well as her fiancé having an affair, begin to spread...

In the end, she loses everything when her fiancé commits treason.

In her last moments, she turns back time using the relic of the first emperor. In order to stop the main culprit, Regina declares that instead of a maniac, her brother will become a love-crazy fool.

“Only you can be my servant.”
Renee, a girl cursed with immortality, was fired from her job for being too creepy and is now seeking employment. One day, she is recruited to be a servant for the prince. However, the prince was imprisoned due to his “curse of poison” that kills everything he lays his hands on. These two lonely individuals who hold contrary Curses are brought together by fate in this master-servant fantasy!

High-school student Hasumi-chan is drawn to Khomura-sensei, a young, socially awkward biology teacher generally seen as weak and boring but recognized by her to be kind.

Ako Kobayashi is a high school girl eagerly awaiting her prince charming to sweep her off her feet, but she has to overcome one small problem: she is so afraid of guys that she breaks out in hives whenever she comes near one. She even rejects the popular Kei Kitaooji who is the first guy to ever ask her out. However, after Kei learns of Ako's condition, he comes to school the next day dressed as a girl and asks her out again.

Suddenly living together with the most easily flustered man!? A gap love, a difference in age and generation!

Gaku, the somewhat nostalgic young delinquent, showed up in front of Akira, a high school teacher around thirty years old. Moreover, why are they suddenly living together!? This is the heart-throbbing, awkward love between Gaku, a cute, earnest, slightly foolish boy who likes to look good, and Akira, an older woman who unconsciously leads him around the nose!

Lucia grew up not knowing she was a princess. But when her mother died, she entered the palace and had the chance to see her entire future in a dream. In her dream, when she reached 19 years old, she was auctioned off to the bidder who offered the highest dowry. Her life became miserable from then on. When she woke up from her dream, she was determined to reshape her future, realizing that she had plenty of time before the crucial turning point. Thus, she begins her journey to change her dark future.

From Viz:
The more Wedding Peach and her friends Yuri and Hinakiku discover about their new-found magical powers, the more Rain DeVilla and her evil henchmen vow to destroy them. In the never-ending battle between love and hate, three young girls are the world's last line of defense against the onslaught of evil.

Main story is in vols.1-6. Vol.7 is a recap volume.

“Tia, your brother has to do well for you to do well.”

By committing all sorts of evil acts, she made her brother the emperor. But her dedication was rewarded with betrayal. At the brink of death, the one who extended a helping hand was her arch nemesis, the righteous Grand Duke Cedric.

"Devise a plan."
"..."
"I can't think of anyone else who could turn the tables in this situation, Lady Rozan."
"..."
"Lend me your strength."

It wasn't possible to restore the balance of power for an empire that was already falling into ruin, but there was a way... to turn back time before everything went wrong.

With her blood and tears, she sacrifices her own body to cast ancient magic in order to turn back time.

This time, she wouldn't fail.

Returning back to her 18-year-old self, Artezia resolves to become the villainess for Grand Duke Cedric.

"Please ask for my hand in marriage. I will make you the Emperor."

The humorous adventures of a veterinary student, his friends, and his dog, as they learn how to care for all kinds of animals.

I reincarnated into my favorite genre for novels. I became the villainous aunt who mistreats the young protagonist. I felt sorry for my nephew who would grow up as the protagonist in a revengeful plot, so I’ll try my best to take care of my nephew until his uncle shows up and takes him as per the original plot. But then… “Oh, mom!” I’ve become his mother all of a sudden? “I don’t know your circumstances, but how could I bear to separate a mother from her son? Lady, come with us to Vintervald.” Hey, Kim Luka! How are you going to fix this misunderstanding? (Synopsis : Gourmet Scans)

From Shinnen:
Nanoka's grandfather, right before dying, tells her that she's not alone -- she has a brother. But when Nanoka arrives at the address her grandfather gave her, she finds out that there are two brothers there! They aren't related by blood, and Nanoka has no idea which one is her brother. Is it Aoi or Kou?

Aikawa Eri dies in a traffic accident after staying up all night playing an otome game. She reincarnates as Eris, the villainess of her favorite game. In order to avoid the bad end, she tries her best to change the story, but as expected, it’s hard to rewrite fate…

She is abandoned by the prince. Even more, her life almost ends when she is attacked by a gang of thugs, but a young man appears...

Will the antisocial prince change her destiny? This is the reincarnated villainess’s rebirth romance fantasy!

From AQUA Scans:
The curious prince of the mermaid kingdom, Naru, sees a human girl, Nami, and falls in love with her at first sight. Yearning for her love, he seeks a witch to turn himself into a human! But to gain this form, he has to exchange "something" in return...

Tamiya Nika is a beautiful, outgoing, popular high-school girl. She has just the right look, just the right fashions, and is everyone's friend. What everyone at school does not know is how hard Nika works to keep up this perfect image, and what she is REALLY like at home. When not at school, Nika is a scary, sloppy, tight-fisted girl who wears glasses, an ugly sweatsuit, and has her hair pulled back into unattractive buns. She lies around playing video games and reading manga. Her attitude is bossy and cranky, and she travels far out of her way to shop where she won’t be recognized.

Every day, Nika “Switches On” with a strict regimen of beautification that involves primping and plucking and careful dressing. The only person who knows about Nika’s Switched On/Off modes is her best friend, who is also aware of the reasons behind the changes.

However, soon a second person finds out about Nika's personalities - someone who has his own On/Off switch, but in reverse! His name is Kamiyama Arata, and he is a recent transfer student. He meets Nika when she is in OFF Mode, and then again at school when she is ON. However Nika can see that he has his own little secret. At school, Arata wears thick swirly-eyed glasses and messy hair that make some bullies think he is an otaku. However, at home, he ditches the glasses and is downright gorgeous! He is just the opposite of Nika, but why?

Chiyoko, in her second year of high school, transfers to a co-ed school due to her dad's job transfer. Since she's only attended an all-girls school since junior high, she excitedly plans to fall in love in her new school. Out of the blue, she begins to see the love meters of 5 hotties and an options window as if she were in an otome game?! She encounters various types such as a glasses boy, a playboy underclassman, and a mysterious senior. Meet-cutes with boys come one after another. This is the beginning of a real otome game school life!

Rin Kagamine's childhood best friend, Shun Otonashi, transfers back to her middle school just as she's in the middle of puberty. Shun's demeanor has changed so much since they were young that Rin is confused as to how to talk to him. On the way home from his first day of school, Rin suddenly asks him why he's returned to the neighborhood. He answers, "I wanted to see you again, Rin," as a joke. At those words, Rin's heart begins to thunder... The long-awaited manga adaptation of the Vocalo P and Junky song with over 2.6 million views about life as a teenage girl who can't be honest with her feelings!

Miku has loved singing since she was little. She earned a magnificent victory in her audition and stepped into the world of idols. Finally, she became a top idol, but the office she belongs to has forbidden any kind of romance. Soon, Miku starts to wish that she could fall in love like a normal girl. Then, one day, she meets a mysterious boy named Len in a dream...

“Your names will be Arjen and Arien.”

We were just like any normal twins going to high school, but then we lost our lives to a sudden accident and our second life as twins began!

And so we live inside an abandoned palace along with an abusive mother and a cold-hearted emperor as a father.

But on our 5th birthday... The king suddenly wanted to see his children.

"Why so suddenly?"

We can only trust ourselves!

Initiate the twins' Project Survive the Palace!
Links:
Promotional Video: https://www.youtube.com/watch?v=_cWvQ8JJxDw
Original Web Novel: https://page.kakao.com/home?seriesId=51841156