Pada tahun 2035, Pasukan Ekspedisi Militer Antar Dimensi Republik Indonesia dibentuk untuk menanggapi penemuan sebuah Portal antara dimensi. Portal ini membawa mereka ke Dunia baru yang berisi berbagai mahluk Fantasi seperti Elf, Naga, Orc dan masih banyak lagi! Ikutilah petualangan pasukan Ekspedisi Indonesia dalam melakukan pertukarankultur, melakukan penelitian, mencari sumber daya dan bertempur melawan ancaman yang mulai bangkit. Akankah portal ke dimensi lain ini dapat membawa ke Masa Keemasan? Atau malah membuat mereka musuh bagi seluruh dunia? Mari kita saksikan bersama!

Getting Isekai'd to another world is indeed awesome, especially embarking on an adventure as a hero to defeat the Demon King, who turns out to be a woman, and making her part of your harem. It is truly the dream of millions of people hoping to be Isekai'd to another world. If Reinhard were to get Isekai'd like that, he might smile for the rest of his life. However, fate has other plans for him, as he becomes the unfortunate isekai victim, landing in the rabbit hole known as the moonlit world. With numerous psychopaths roaming around to fulfill their dreams, he must strive to defend his small life in this chaotic world, especially when the world is set to last only another decade. Fortunately, luck from nine generations of his family comes to his aid in critical moments. Finally, he gets help to secure his small life: [Ding!] "Eh? Has my help finally arrived?" [Congratulations, Host! You have been chosen as the host of the Antagonist Simulator System!] "Finally! Fina-... wait... What do you mean by Antagonist? Shouldn't it just be a Simulator without an Antagonist?" [As the name suggests, the Antagonist Simulator System is specifically designed for individuals with high aspirations to become antagonists, and you have been selected to be the Ultimate Antagonist! Congratulations, Host!] "Huh? Ultimate Antagonist? Wtf? How does someone as gentle as me fit as the ultimate antagonist?" [Not so.] [Host, you undoubtedly possess a strong motivation, clear plans, firm will, undisclosed secrets, outstanding execution, remarkable personality charm, and the determination to subvert the world.] [Undoubtedly, you are the perfect candidate for the ultimate antagonist.] WTF?