This hefty volume is THE ~PTH TREATISE, which chronicles all the undulating intricacies of the ancient programming language of the same name. ~PTH was a shockingly rare joint effort between a surfacedweller and a nymph, developed long, long ago. The fact that the surfacedweller was an omnicidal madman, and the nymph a megalomaniacal heretic, only serves to increase its mystique, its illegality, and, most importantly, its breadth of scope.
~PTH is an unholy chimera of primal magic and stunningly intricate logic, and was apparently some kind of ruthlessly protected state secret up on land. You don't know what TC did to get his hands on it, but the effort to develop the game really took off after its discovery. The two of you have been sending it back and forth for ages, now, each contributing a different perspective to further your mutual understanding of the concepts outlined within.
Right now thinking about that kind of stuff is just going to stress you out, so you opt to leave it closed. It makes for a better cushion that way.
