Eiro flipped through the books in front of him, finally a bit more relaxed. Now that he found out that, while not particularly natural or normal, what was happening to Leon's body was absolutely fine. He wouldn't end up damaged by this long-term. All that Eiro had to do was make sure that he found out what tribe Leon was from, since their maturity-phase was often quite different depending on the tribe.
This mostly had to do with whether or not their 'guardian spirit', the animal that their tribe was based off, was a herbivore, carnivore, or omnivore. Of course, since they weren't animals, beastmen didn't have to worry about having a one-sided diet.
A carnivorous beastman could eat fruit and vegetables perfectly fine, but they still required a lot more meat in their diet while their bodies were changing during their maturity phase, or else they could fall sick as well.