You are an average, run-of-the-mill office worker who lives a drab and dull existence. Until... you get the balls to leave a message on a "homestay" website. This site is specially designed for women looking for a place to stay. Eager to meet your first visitor, you open the door and see a female wearing bizarre clothes, who claims to be a kaiju princess. Can anyone say... psycho?

Nevertheless, you two make a deal: You will provide shelter and basic necessities for the young lady, and the mysterious stranger will provide you with... *cough*... services.

Unfortunately, it soon becomes quite evident that the woman is indeed an alien invader. And to top it all off, she can summon kaijus and command them, which she does to carry out her mission... to destroy Earth! Even if you kick her out or manage to get her off the planet, the invaders will only send more ruthless kaijus to attack.

There's only one way to help save the planet: Make sure she meets the "minimum destruction requirements" set by her alien overlords. If you can do that, you can stave off utter annihilation. And thus, you join forces with the huge-titted kaiju princess.

Meet your destruction quotas in the time given and minimize damage and death in the city. At the same time, you need to make sure government agencies aren't onto you. There's only one thing that's more important than all that... living a great life and having fun with your hot kaiju companion!

 

◆身为一名普通上班族的主角一直过着毫无变化的平凡生活，某天心血来潮在离家女性的寄宿网站上登录了住处的主角很快迎来了寄宿对象───身上披着怪兽大衣，自称“怪兽公主”的奇怪女子。
主角与奇怪的女子进行了交易。

在寄宿期间，主角须提供她住处以及照顾她的日常生活。
在寄宿期间，她必须向主角贡献身体。

◆然而在共同生活期间，主角却发现了怪兽公主竟然是拥有招唤怪兽以及指挥怪兽能力的外星侵略者，而且就算驱逐她，她的星球也会立刻派遣出新的侵略者！为了让这名工作上应付了事，只需

 

要协助她完成最低业绩目标就不会进行额外破坏的外星人留下来，主角自愿成为了怪兽公主的协力者……

 

在有限时间裡缴交业绩、减少城市毁损与人员伤亡，迴避官方组织的击退怪兽部队，并且保护星球，主角将于怪兽公主展开一段奇妙的同居生活。