In Australia Fantasy generally refers to the drug GHB or 1,4 Butendiol. I've never heard of this drug being found in pill form though. Neither are the traditional affects of GHB or 1,4 Butendiol ever really 'chargey'.
'Fantasy' is usually sold in liquid or powdered form, and has very small margins when it comes to dosage levels.
you might want to try requesting information in the Europe/UK/Africa disscussion to see if any UK residents can shed any light on what might be regional slang.
though saying this, the problem with regional slang is that it can differ greatly amongst social groups even within the same town. So you may not recieve much in the way of acurate information.
If the pills have any marking on them i would recommend heading over to
pill reports and trying to match an image/description in the UK area.
sounds alot like your DD might be getting a wee bit creative in trying to move his product by giving it a flashy new name, that actually has no bearing on it's contents.
I would definately reccomend/support you testing it before consuming it.
better safe than writhing around on the floor, slowly turning a striking shade of blue