Listen, black hole soul is not as lugubrious as it may sound.
Yes, black holes do have a propensity for devouring anything within the event horizon, but since that is pure energy it’s not black at all! You see, black hole is actually a misnomer as they are the brightest objects in space in terms of non-visible radiation.
Also, some quantum mechanics magic predicts that they generate a massive amount of energy. So a black hole soul is one that absorbs all that is good and pure and disperses it back out for others to absorb.
And it was the first thing that popped into my head. Not crazy about it – but too late to change now.