Mystery: I'm secretly opening my vest

Master of Mysteries.
The protagonist just thinks that he is playing a game, he can play more characters, there is a system, the protagonist has no name, and may even have no gender.
Character cards (approximate order of appearance)
Tom - common name, born prisoner (cannon fodder).
Vanessa Augustus - the darling of fate, the ordinary girl who wants to cry when she sees a baby snake?
Arthur - the shining knight.
······

Novel Keywords: Mystery: I'm Mysteriously Opening My Vest No Pop-Up Window, Mystery: I'm Mysteriously Opening a Vest txt Complete Works Download, Mystery: I'm Mysteriously Opening My Vest Latest Chapter Read