All hearts are one,
one heart is all.

In other words,
the Kingdom's heart—"Kingdom Hearts"
That is the great heart.

And hidden within
is great darkness…

—Kingdom Hearts: Chain of Memories

Kingdom Hearts: Wings of Memories; Tsubasa: Another Chronicle © kurotsuba.

Tsubasa Reservoir Chronicle, xxxHolic © CLAMP;
Kingdom Hearts: Chain of Memories © Square Enix, Disney.