Rhythm to the Fray (слэш)

It's not a mark or a thread that distinguishes a soulmate; instead, it's a physical sensation, a bio-resonant connection—a rhythm to your breath, a cadence in your blood, the echo of an extra pulse inside your chest that proves your heart's not quite beating by itself, anymore; that it was always waiting for a matching set of notes to make a melody, and now it's singing, now it's soaring. Now you're whole.
But when what you've got is a pair of tricky lungs, faulty blood, and a bum ticker, it doesn't matter how strong your soul is: the harmony will barely rise above a whisper, the resonance will almost always strike too weak. So it's no one's fault, really, if a person misses the fact that his soulmate's standing right in front of him.
It's no one's fault if it takes the better part of a century to finally see.