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The first time you go to Kaminko's house, Chobin (the man with swirly glasses) will challenge you to a battle, mistaking you for a burglar. He should go down easily, as his only Pokémon is a weak level 5 Sunkern. After you beat him, he will let you into Kaminko's house.

Once inside, he will show you the screen hanging on the wall in the foyer, and tell you that it conatins about a dozen entries on Kaminko's "marvelous" inventions, which are really pieces of junk. But the more imortant thing to see is Jovi. Head to the left room, and you will see Jovi next to Kominko. After some dialog, you "covince her to take you home", even though you know the way. Now head back to the Pokémon HQ.