The love interest character's clothes got destroyed due to plot reasons, so she had to fashion new ones that amount to basically a halter top and hot pants that she wears under her full samurai armour. The main character goes 
while another one explains how being half-naked will somehow make her much more mobile during fights. Why aren't the male characters stripping down to their underpants then 
What makes this especially aggravating is that her original outfit was a really cool and non-horny female samurai design 
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Onimusha 2 was absolutely chock full of crusty NPC ossans running around looking just like that, lol
This lady very pointedly does not wear a breastplate though. It's almost the opposite- her legs, arms and even her fucking neck are very well protected but her torso isn't. I mean, her original outfit didn't have a full breastplate either but at least the undersuit looked practical. If they wanted to do the silly sexy lady samurai thing they should have just gone full Lady Kagami from Tenchu 2
I could totally go for some more Tenchu at this point.
From Software owns the rights and Sekiro started out as a Tenchu reboot, apparently
I just wanna toss poisoned rice balls onto a hapless guard's patrol route from a rooftop and watch him keel over dead when he happily eats them