I found this by accident. It may be simpler than I thought, but here is how i do it.
You need all the raposa rescued, cause you need the raposa you rescue with Dr. Cure.
To the bottom left of the 4th world gate, theres an old man raposa, and a normal male raposa. Talk to the old man 4 times, then talk to the other raposa a few times. It doesnt always work, but sometimes the old raposa vanishes while your talking to the other guy! He fades out, sorta as if he were going into a building. Only thing is, he just stands there and poof! As far as i know, it only works with him, and i cant seem to make it work 100% of the time. And if you go somewhere else in the village and then go back, he returns. Its really creepy! 0_o