it has a little bit, mostly in terms of how he'd fight and with what weapons. the protagonist is mute so there's no characterization to really be found there lol. it's also fun to have a visual of what he looks like in a more realistic style.

there's a couple of weapons that i like using in nioh that apply to touma:
fists: i already knew i wanted touma to be a deadly martial artist before nioh, but seeing him punch the shit out of demons cemented it for me lol. he wouldn't be a super speedy fighter like in game though, realistically he's more calculated and precise with strong individual blows/grapples and such
splitstaff: i like the idea of him practicing with it as part of his martial arts training. more of the normal staff variety though (lunar), not the separating kind
odachi: big weapon for a big man. i just think it'd be funny if touma practiced with it in his spare time, not as a super practical weapon for him to use out on the field (he's a ninja after all) but for his own self-improvement.