Roleplaying's something that makes me particularly eager to translate! I like when fans and RPers really care about the source material. Animanga Natsuno's a pretty different character from his novel self, but I hope it's still useful to helping you feel the Sotoba setting he's in.

Actually, I personally think Natsuno's pretty much the same between the three versions, and that Tohru, someone close to him, is different, and the things which happen to him are different. But I consider the novel insight into animanga Natsuno, myself. His seiyuu did a really good job bringing his maturity and callousness while also capturing the gentleness in the novel narrative and some of his more age-appropriate youth and mysteriousness.

Anyway, I hope you enjoy him even more for this and that it's useful to you!