Hello, I'm Tobi.
But at the same time I'm using lot more names, so You can basicly ignore my name
I think I could assume that what You refer to is either gloss effect on legs or Skin details.
Next time when You ask question it would be appreciated if You specify exactly what is reference of Your question.
The better You write Your question the better answer You will recive, so it's worth - i guess.
I will assume that You refer to gloss, as it's especially visible on the picture.
Way to achieve it is many, especially good method is by using KKUTS and/or KKUSS.
1) KKUTS High Color
2) KKUTS High Color Mask
3) KKUSS + PointLight in Chara Studio
This is the ultimate pack to manipulate glossines on the skin in Koikatsu.
KKUSS have special Spec that makes things blinks a lot and creates very sharp gloss, see Yourself:
View attachment 3108171
In this scene I intentonally reduced Directional Light to .88 so dim
Light a little so You can easly see Gloss, it also have similar skin color
To scene You are referencing to
View attachment 3108172
First, add KKUTS as Your main material, then duplicate it and replace
duplicate with KKUSS_Alpha, set Alpha slider to 0 and then play with
SpecularPower, You want to add few point lights in the scene like I have.
Depends where You place Point Lights You will get highlights in different positions.
To add Point Light go ( Add -> Map Lights -> Pick PointLight or SpotLight )
View attachment 3108202
Ofc. everything is matter of settings You gonna use.
But basicly effects like that are Specular and High Light settings in Materials.
View attachment 3108207