Overhead
In this ninja world, heartbeat is a physical law. Everyone has only one chance in his life to send out the "first echo", which is the frequency of soul trembling. Most people can't hear it, but only a handful of "listeners" can catch it. Once the echo is sent out, all the entanglements, loves, hates, and fights in the rest of life are essentially the infinite echo of that first sight. The stronger the reverberation, the deeper the bond, until death cuts it off.
Intention: [The echo of the first sight × the echo of the rest of my life]