The girl using the Hermituar set with almost the same weapon I have now (Devil Slicer)... is just about to be attacked by either of the bosses: Kut-Ku, or Raithan?! (see that incoming huge wyvern above? and to worsen it, this one looks more buff as like Raithan instead of a Kut-Ku.)

It can't be a Rathian, look at the end of the tail.

Maybe a Gypceros...?