Nangong Rui didn't expect that the truth of his situation was all because of elementals. After all, humans are incapable of seeing much less having something to do with them. Human's affinity is with the beasts. Likewise, Elves affinity is closer to the elementals than the beast. That's why former Elf King Vega never summoned any beast as he is a Spirit Tamer instead.
The classifications of a Spirit Tamer is similar to the Beast Tamer. The only difference is that they tame different kinds of race. The former control elements while the latter is the strength of the beast, though they are both tamers, this difference cannot be changed.
