This is done by modifying the texture shared with npc.
Because npc has no body other than head and hand.
The npc I am modifying is making a nude body and adding it.
So, there is no body in unmodified npc. I seem to have misunderstood.
psw_00_ub_0001_ao.dds is a texture that creates a shadow on the body.
Please do not delete this.
Otherwise shadows will be created.