It means related with the demon or the devil. Demonic, Satanic, infernal, mefistofelico, perverse, I malignant, malicious.
diabolical is incorrectly written and it should be written as "SON OF A BITCH " being its meaning: 60; /br 62;MACHIAVELLIAN person who enjoys harassing of the other's way convenient and LAPPED to pass as a harmless, but bad Undercity, when someone crosses you or falls ill and wants to remove it from the road, because in the background are people cowards will not front.