To flirt with Death is to ask him to love you, and if Death loves you, he has to choose between killing his lover and watching them become a monster.
One day, you must die. Maybe not right now. Maybe you could have a few more years, given a proper vessel and some careful planning. If you’re young and shouldn’t have died at all, perhaps a few decades. But what then? When those years are up, what does Death have to do? The first option: He must drag you, his dear beloved that he cares so deeply for, to the other side while you kick and scream and fight and accuse him of abandonment, of hatred, of cruelty and malice, making your final moments dark and his last memory the pain of you spitefully spitting in his face. The second: Death must watch you as the seams of your soul begin to split, as the edges of you rip and fade, as your mind decays into a starving vacuum devoid of thought and feeling, as your heart is overcome by a voracious hunger for other life and a desperate, nagging need to steal it from those who have it.