Twenty year old Naofumi Iwatani is a college student with an allowance that lets him stay at home enjoying an Otaku life. One day a book drops to the ground while at the library which tells of four Cardinal Heroes being summoned to the other world of Melromarc; each wielding a different weapon - sword, spear, bow and shield. Other than...

A retainer-like device known as the "SCM" is being sold on the internet and rumours have it if you wear it and challenge another person that's also wearing to a duel, you can turn them into your slave when you win. Ohta Yuuga comes across Eia Arakawa one day after dumping her best friend. After discovering how daring and smart she is...