Sword and Collar of Slave Trader

The hero who decided to turn into a slave dealer with an idea. - With Yuma, a girl with cat ears that I bought as a starting point, as an assistant, I - decided to travel around the kingdom to meet the requests of people seeking slaves . - "If you defeat the thieves and dangerous sub-humans yourself, you can get slaves without spending money!" - However, the protagonists who stopped by Yuma's hometown while buying and selling slaves were involved in an unexpected conspiracy