A game with death

This is a short story I wrote when I was very bored. It is based on a writing prompt which goes something like this.
"Checkmate, " you say, a smug expression on your face. "Finally," says death. The smirk is wiped off your face as the grim reaper removes his robe and hands you his scythe, "it's been 400 years since I beat the last guy"
TW: Mentions of sexual assault/rape, suicide and self harm, loss of a close one