Mushoku Tensei - Volume 21 Side Story — The Mad Dog and the Child of God

Wazu was an ordinary townsman who shut himself off in the “mountain” because of an unfortunate course of events. After 2 years, he decided to come down from the mountain to meet with people. But there were various misunderstanding about the “mountain” which he shut himself off in. And then he repeatedly had encounters with people. And after that. . .

Three years after graduation, Chu Mo, who could barely maintain his most basic life, opened the Shenhao system, and an unlimited and safe bank card appeared in front of him. start a company? to invest? buy stocks? These in unlimited banks…

- Description from novelbuddy

The mountain village boy accidentally got the fairy gourd, and he rose step by step to cultivate immortality and longevity.

Ripe elixir, mortal flow.

- Description from novelbuddy

The second prince has come of age. To celebrate the advent of such an occasion, the search for a suitable bride began. My younger sister was expected to go to the Royal Palace as a candidate. However, despite this, she eloped the day before her departure. I, the older sister she left behind, looked almost exactly like her – so much that we were often mistaken for twins…

One month, right? For just one month, shall I substitute in for my sister?