Oathbreaker: A Dark Fantasy Web Serial - 1.39: Departure, Duty, Dream

The starry sky was resplendent, filled with tens of thousands of Tribes!

During the Great War of the Immortal World, when the race of the God Realm was annihilated by the sixteen Immortals’ Alliance, one of their clansmen accidentally fell into a Purgatory of three thousand years under the Immortal World, lucky enough to survive …

A few years later, in a mysterious hidden family in the Purgatory World, a crippled youth who had been abandoned by his family had accidentally awakened a dragon vein …

- Description from novelupdates

Su Bai, a novelist from Earth accidentally fell from the top of a cliff.When he woke up, he realised he had already transmigrated to another world. Furthermore, this was not just any world. It was a primitive other world with Humanoids.With his Daily Assistance System and extensive knowledge from modem society, some of which he learnt from being an author, he led his primitive Tribe out of poverty. There, little by little, he started to transform the era, to advance it forward!Uncovering mysterious of Shamans! Meeting more beast eared women! Farming!

Things were going great for the demon Bael-Sharoth until a little girl summoned him to open a jar of tomato sauce. Now he's trapped in the human world along with his arch nemesis the beautiful and capable Maharet Flameheart. Life isn't easy for a demon in a small town. But at least the parks are hellhound friendly and the werewolf at the local bookshop seems nice enough. Bael and Maharet must find a loving human family to take in this powerful young witch before time runs out or risk being stuck on earth forever.What to expect: A cozy found family romantic comedy in the style of Good Omens and On a Pale Horse.Gruesomely Wholesome. Enemies to Lovers. Strong Male and Female Characters. Loyal Hellhounds. Sassy Hellcats. A happy ending.

…but it seems pretty doable.