Shinjuku (Sub-Singularity I): Shinjuku Station (Free Quest) is the best AP-saving & time-saving location to farm Magical Cerebrospinal Fluid. You'll get around 6x Magical Cerebrospinal Fluid by spending 210 AP.
Rashoumon event (Ibaraki Douji event)
Murder at the Kogetsukan
Inheritance of Glory
Dragon Fang
Gandr
Ereshkigal
Arthur Pendragon(Prototype)
Gorgon
Black Holy Grail (The Black Grail)