[He's wondering just how exactly he'll know... but he'll trust that it'll be obvious enough. Will it? There's only one way to find out. Kain shakes his head to Atem's question, hesitating just a moment in indecision about which of the hearts he ought to try.]

I'm afraid I'm not familiar with this tale. Is it well known where you come from?

[There's little difference he can see physically between the hearts. It's definitely unsettling to be doing this, and knowing that Law has held their lives in his hands all of this time... This might have ended much worse. He frowns a bit, but then finally selects one of the hearts, picking it up with care. He holds it as if it's a valuable that'll break with even the smallest mishandling.]

Here goes.

[Just as cautiously, he moves to bring the heart toward his chest, attempting to fit it back in there. He's not so sure, right now, but it doesn't feel too promising to start with.]

I assume it'll just... reconnect itself to everything else if it's meant to be there?