This talks about Rimuru and his friends spending their free time doing something fun together. A spin-off from the main series "That Time I Got Reincarnated as a Slime"

A man who drove countless couples to ruin in his past life is reborn as the angelic beauty Netora Reiko! But this girl has only one desire and it's "to experience the ultimate NTR!?"
The most despicable yet glorious romantic(?) comedy where an NTR-obsessed TS beauty sets out to deceive everyone around her and mentally destroy her childhood friend in the process!

William is the lone human in a city of the dead. Born with vague memories of a past life in contemporary Japan where he failed to do anything useful, he is determined not to make the same mistake again, and that this time, his life will be lived. But what does that really mean? Raised by a group of the undead, William must discover what circumstances brought him to this city and these people as well as what it means to not just exist, but to live a full life.

"I did it again...!"

The Hero who can't seem to set out on his journey!!

The protagonist, who was reincarnated into another world, becomes a hero and receives the task of defeating the Demon King. To repay the world that accepted him , he decides to set out on a journey... However, he can't seem to leave the first village, as he is constantly tempted by charming heroines such as the female priestess, his childhood friend who is a magician, and so on!

Thus, the birth of the "I did it again...!" type hero!

In another world, the Hero and the Demon King continued to oppose each other. As their great magic collided, the explosion crossed over worlds and destroyed a classroom full of high school students. The victims who died in that explosion will be reincarnated in that alternate world. Our heroine, who has the lowest standing in the class, was reincarnated into a spider. She nevertheless faces this challenge head-on with great determination, and adapts to it surprisingly quickly. This is the story of how our protagonist, who was reborn as a weak spider monster, does whatever needed to survive.

The strongest reincarnated daughter goes on the rampage! A gripping, otherworldly entertainment!

"I wanted to die fighting anyway."

The great hero, who once even killed a god, wanted to fight even in death. What awaited her was her reincarnation as a sickly noblewoman. In the future world, she becomes the beautiful but too weak Daughter Nia Liston, but in her second life, she goes on a rampage in battle, in delivery activities and in academy life!

This is a record of the brilliant battles of the hero who will eventually be known as the "Wicked Rampant Daughter". The most powerful Warriors' Daughter presents the start of a painful otherworldly entertainment!

The Sage Dwight, he along with the Hero defeated the Demon Lord who sank the world into darkness.
However, they were falsely accused of becoming the next Demon Lords because of his power, and were thrown to The Valley of the Dead to die.......
But though his flesh has rotten away, he lives on as a skeleton because of his grudge against the world. Dwight has vowed to deny that wrong world, and with a power that surpasses even the Demon King of the past, and also leading countless Skeletons he's going to start an all out war...!

A man who lost his family and fell into the depths of despair meets his end—only to be reborn in another world of swords and magic as Aldo, the heir of a noble family. He begins a new life alongside his twin brother Elphas and his loving parents. However, haunted by the fear of losing those he loves once again, Aldo starts to shut his heart off from his family. But when the roar of a ferocious magical beast threatens to devour them, the boy rises to his feet— determined this time to protect what he once lost in his previous life. A story of redemption and a second chance at heroism begins!

Da-in, ended up possessing the villain of a story.

To make Stardust — the story's protagonist and his favorite character in a dystopian manga — happy, he resolves to become the villain Egoistic for her growth.

Da-in deliberately causes terror to enhance Stardust's abilities and preemptively prevents all the tragic events from the original story, but in the process, he gains public support while also drawing Stardust's suspicion.

Stardust, who initially opposed him, gradually opens her heart, and soon even begins to show signs of obsession towards him...?

"I also wanted to be... the strongest in the world."

An Arch Mage who died without fulfilling his dream wakes up to finds himself being reincarnated as a member of the imperial family. And what's more is that his new body has a talent for close-quarters combat! This time he holds hope that he finally might be able to fulfill his desire of being world's strongest...

But after reincarnating his new name is Evangeline. Indeed, he had become a girl.
In her princess life where muscle training and fighting are forbidden, Eva brings dumbbells to her room and wields a sword! And before long, she becomes the strongest!?

A fantasy about a tomboy princess' rise to the top!

A high school girl reincarnates in another world as Lily. While she occasionally reminisces about her past life, she is now known as "the Maid of the Royal Family," after helping to rear the lady who eventually married the crown prince. One day, the court magician Leonard suddenly requests that she acts as a mother for his adopted daughter Jill.

Oringinal WebComic / Original Web Novel

Ragna, the heir to a frontier noble family, is a reincarnated former Japanese citizen who realizes that the world he now lives in is the setting of an otome game. Dreaming of a carefree life as an adventurer, his plans are derailed when a war takes his family, forcing him to take on the responsibilities of managing his family’s lands.

Struggling with the unfamiliar duties of a lord, his already chaotic life takes another turn when an unexpected engagement to a noblewoman from a higher-ranking family is arranged.

To his surprise, the bride-to-be is Alicia, the "villainess" of the otome game’s story — a character destined for heartbreak, a demonic pact, and ultimate destruction. Now sharing his life with someone fated for tragedy, Ragna is swept up in the wheels of fate.

Can he rewrite the predetermined outcomes of this world and secure a peaceful life for himself and Alicia?

Chimera hunter Number 17 has spent decades hunting monsters. On his latest mission, he’s ordered to ensure the human hunters’ escape and never return to base. In other words, he’s meant to die. As his body dissolves, his life flashes before him: kidnapped as a boy, forced into endless battles, reduced to a mindless weapon. But against all odds, his body reforms into his human form. No longer Chimera Hunter Number 17, he stands before a vast open land on his own two feet as Do-un Cheon, a human, ready to start his life anew, making friends out of monsters and building the family he never had.

Born as the Thirteenth Prince, Noah was originally in a position removed from the imperial succession, so he freely passed his time in the fief granted to him.

However, the Crown Prince died before the Emperor. The imperial succession would be fairly contested among the remaining princes.

Noah, being the strongest despite living freely, overwhelmed the other princes and eventually became the Emperor with the most power in the world.

Makia is a noble lady descended from an infamous witch. Thor, a boy who was raised with her and came from another world, is chosen to be the knight of the "savior". The two are forced apart and to see Thor once again Makia aims to be the top student at Magic School!

Average high school student Mikagami​ Kouji is a hardcore gamer. One day he gets isekai'd and he only gets the skill "copy" which is apparently useless but we all know it's secretly OP or something. He's enslaved to be a gladiator by his summoner, the big booba, head priestess Zayd. He has to fight in the Colosseum and if he loses he gets raped.

She transmigrated as the opposing boss in the novel, but she was wiped out by the male lead. Fortunately, she reincarnates once more, but back to the past, when the male lead was still young! Looking at the pitifully weak male lead, she was troubled by a dilemma. Should she: 1. kill him, or 2. raise him up and openly ask for treasures from him. However, since she wants to get all sorts of treasures from the male lead, she chose the second option. Things don't always work out though, as she accidentally raises a sheep up to be a big bad wolf.

Master? Want treasure? Let's cultivate together, but alone, just us two, then.

Alban realized he had been reincarnated as the villainous noble in a certain novel. Just as he began training in swordsmanship and magic to avoid defeat by the protagonist, he learned that Leticia, a noblewoman surrounded by nasty rumors, was to become his wife! He was nervous about what kind of "evil woman" she might be... but, upon meeting her, he found an incredibly pure girl — angelic, and exactly his type! Alban, forgetting all about avoiding his doom due to her adorableness, resolved to take revenge on the mastermind who had set up his beloved wife! Using their villainous reputation to their advantage, they set out to lure the culprit, but... will they succeed?

When he realized it, the protagonist was in another world and had become a sword that was stabbed on an altar in a great plain, crowded with devil beast. The world he was in had a game like system; HP, MP, Strength, Vitality, Agility, Intelligence, Dexterity, Titles and Equipment. Following his instinct as a living sword, he traveled to find the one who could be his wielder, until he met with a cat girl that was about to be attacked by a bear type devil beast.

Orginal Webcomic

Fujinomiya Soujirou is transported to a fantasy world with only his Daisho (pair of samurai swords) in hand. The katana can talk and swiftly informs him that it is Hotarumaru, the legendary national treasure of Japan thought lost during World War II. The wakizashi is to young to have a voice, to Souji names it Sakura. This is the story of Souji and Hotarumaru's journey through a new world as he seeks to achieve ... a sword harem?