MTL - Immortal Becomes a Stay-at-home Dad After Return - ~ 478 Miss, do you want to learn martial arts?

In a world where dungeons were an essential part of it, Rein was trying to conquer as many as possible. They were the key to gain powers in the fastest possible way. So, to reach his full potential and to become the strongest, he became a great dungeon conqueror.With his trusty friends and lovers, he was definitely going to reach the peak alongside everyone. Join Rein and see how he went from strong to stronger and then the strongest.__________________1. The harem would not be too large(I'm not sure how many but probably just 4-5 main and few other here and there). All the girls would be getting their time and story.2. The story is starting when the MC is in the middle of his growth stage and not at the very beginning. But his beginning will be mentioned in the story in some form.3. I don't think I need to mention this, but obviously it will not have any NTR, rape or that kind of stuff. It is actually quite a wholesome story focusing mainly on adventure, action and bit of romance and slice of life.

800 years ago, 3000 dimensional gates opened across the entire world. In that moment, it was as if 3000 different colored eyes opened across the world as hordes of monsters swarmed out of these gates like tears.

Some could destroy city walls with one strike; They had bodies the size of a giant and fed on humans

Some latched onto humans, absorbing their bodies’ nutrients and enslaving humans

Some infiltrated the humans’ cities, disguising themselves as normal human beings while feeding upon human blood to sustain themselves.

In a night, the Human race fell to the bottom of the food chain.

The world had turned into a paradise for monsters…

- Description from Novelupdates

[Volume 1: Dante Blackthorn]When Anastasia and her sister Marianne are captured and shipped across the seas by pirates, they become commodities to be sold in a distant land. Marianne is taken as a courtesan, while Anastasia barely escapes a terrible fate by pretending to be mute. She is forced into the lowest ring of servants at the royal palace, where she endures a life of servitude and creates beautiful artwork to mask her pain.Despite years passing, Anastasia has never forgotten her sister's promise to return to their family together. However, with her movement restricted and the guards vigilant, escape seems impossible.When Anastasia comes into contact with the Forsaken Prince, her life spirals out of control and she triggers a Crux of incredible proportions. Now battling her own inner demons while navigating the treacherous politics of the royal court, Anastasia must confront the truth about her sister's fate and make a choice that could alter the course of an entire kingdom.[Volume 2: Emily Blackthorn]Princess Emily's life takes a turbulent turn when she is rejected, leaving her heartbroken and her soul at the brink of corruption. In a desperate bid to save herself, she journeys to the West.Enter the Storm Prince, a charismatic archdemon with striking blue eyes, with a saint-like smile. Emily had hoped she'd seen the last of him, but fate has other plans. As if her soul dying isn’t enough, someone wants to steal it!Caught between the suitors and the haunting nightmares that have plagued her since childhood, Emily begins to see Raylen in a new light. The blue-eyed demon may not be the monster she once thought.

The most powerful sword was broken in an ancient war and now its spirit is reborn in a common sword and bought by a girl named Li Qingming.The sword spirit senses that Li, though weak now, boasts some traces familiar to it, which remind it of its former owner and his friends.