Justification for Dante's resistence to reality warping, life force absorption and transmutation

[Twellas]

The DMC3 key for Dante shows these resistences with the reason that "Demons are stated to be resistant to the Beastheads assimilation process, which includes those abilities". Am i the only one who's confused by this? I don't recall the beastheads being in DMC3 nor them being in the manga. Are these resistences from the novel? If yes I think it would be good to link the source for these abilities since they are EXTREMELY important in battles. Also why would the demons being resistent to the assimilation mean that the demons are resistent to these abilities?

 

[Oliver_de_jesus]

If the demons resist the process of assimilation, the dante himself affirms it. But the resistance of vital energy absorption is from Nevan.