F-Gel

F-Gel is a fictional drug which appears in K. M. Hirosaki's Blue Forest series of stories. Properly called the transdermal form of Flocciparacetylamine, it is a blue gel-like substance typically sold (at exorbitant prices) in translucent foil packets.

It is absorbed through the skin (the inner ears are a popular location for this, due to the absence of fur and the proximity to the brain) and has the effect of heightening sensory awareness and the appreciation of it. Any sensation, even discomfort, is intensely gratifying and the user's conscious responses are impaired by the deep desire for physical contact.

Self-application apparently dilutes the experience; typically a user needs a second party to apply the drug to them.

The drug is highly addictive and extremely expensive. It appears to have a cumulatively taxing effect on the nervous systems. Withdrawal symptoms occur increasingly rapidly and include lapses of consciousness, trembling extremities, intense anxiety and impairment of motor-functions.