An Asian girl with big boobs and/or ass. Finding Asians with these assets is difficult, thus the "rare" part. Also based off the item in the Pokémon series that is hard to find.
John: "Yo did you see that Asian girl?!"
Tyrese: "Yea bruh she's a total rare candy. Biggest tits on an Asian I've ever saw."
12 step recovery jargon referring to someone new who talks about how great life is, now that they'resober. Usually meaning that the person is out of touch with reality.
The new guy seems pretty happy for a dude who has no job, no money and no family. He must be on a pink cloud.