What does a centaur symbolize

What is the symbolism behind depicting Kaga Ryosuke as a centaur when using his invisible dictionary?

In Greek mythology, the centaur is a creature related to both basic instincts and wisdom (lust or, in the context of perversity). They are associated with the god Dionisius, the god of carnal desires (sexual drive) and the carousel.

From Monstruous.com:

The evil centaurs are the opposite of knights and horsemen. Instead of dominating or taming their instincts, these centaurs are ruled by them. They symbolize violent lust, adultery (...)

From the Wikipedia article on centaurs:

Like the satyrs, the centaurs were notorious for being wild and lustful, overly indulgent drinkers and merry-go-rounds, subjected to violence when drunk, and generally uncultivated offenders.

So the centaur's first symbolism relates to the fact that Ryosuke releases his perverse mental energy.

The most famous centaur is Chiron and according to Wikipedia again:

In contrast, Chiron was intelligent, civilized and kind (...). Chiron, a great healer, astrologer, and respected oracle, was considered the first among the centaurs and was highly revered as a teacher and tutor.

This could be related to the fact that Ryosuke shows his great knowledge or wisdom by taking on the contents of the dictionary.