I think the best way to sum up the definition of a soulmate for is in the immortal words of John Birks Gillespie when describing his friend and musical sparring partner Charlie Parker: “the other half of my heartbeat.”
For me the concept of a soulmate isn’t one of a romantic notion but an intellectual one, your soulmate is the one who challenges you and vice-versa. A sounding board for your mind which beats thoughts through your mind, much in the same way a heart does with blood and your body. The nearest I probably have got to finding my soulmate is probably with Amy and to a certain degree Philippa, both of whom I can/could play intellectual Tennis with batting ideas to and fro, often with very entertaining results.
Well to bring this rather short post full circle, it maybe a grainy bit of footage, but here is Professor Bebop himself with the other half of his heartbeat: