Summoning

In a Universe that, apparently, has three realms, the now Yonko Luffy is summoned to the human realm to do a job. But something goes terribly wrong, and he ends up being rescued by Trafalgar Law, a realist who hates anything out of the ordinary.
And Luffy? Yeah, our always sunny and cheerful demon Luffy, decides to make Law his mate. And into a half-breed. Aaaand... just somehow fuck up his whole life.
But did anyone ever ask Law what he thinks of all this? And why don't seem his roommates Hawkins and Kidd surprised at the demon in his bed?