Monsters found mainly in The Cords, Rapunzels are something between Neurodonors and Axioms, but not enough of either. A rapunzel is a human who had a neural-interface implanted incorrectly, and has gone crazy as a result. Neural interfaces as a whole aren't widely used anymore, unless they're full-neural, full-replacement (such as in the case of the neurodonors) or they're attached far enough away from the spine that they don't cause interference (such as axioms, with their replaced limbs). Despite them being rare, people still have neural interfaces implanted for the same reason they do drugs; that direct line allows you to completely control the hormones your brain releases.
Because Implanted Partial Neural Interfaces (IPNI's) fell out of use, it's very hard for anyone with one of them to find a legal place to spark up. As a result, IPNIs use any wires they can find and connect them to their head in hopes of getting high. As this practice is wildly unsafe, it's bound to happen that eventually they'd find a wire that is too high voltage for their IPNI, and it short-circuits something in their brain, burns it, with unpredictable results. Once this damage has happened, they're termed "Rapunzels" in the same way one would say "crack addict".
Rapunzels are characterized by their gaunt, sickly appearance, headdress of wires they've ripped from buildings, lax muscles, and unpredictable aggression. If they've completely destoryed their IPNI, they can be found chewing on wires and shocking themselves, hoping to feel something again. If they haven't, they're found hanging like gargoyles on the edges of buildings, plugging into any wires they can.
If you find a dead rapunzel, they usually either starved to death, shocked themselves, or blew out their IPNI.