you can try to look for model first , if there are none , i will try to create her myself .
( the link you sent triggered me lol )

as i know , you will need a plugin for that game ( koikatsu or shoujo ai or whatever ) to export their model . but it needs some sort of installaion and compatibility . once you have the model , just upload , no need for a 3D application .

well unfornately, that's the only model i found so far

maybe some chinese have better model

well then there is a bigger problem . model exported from Illusion's game are very detailed , make it much more likely to crash l4d2 . also many element will be lost ( texture system , bone + rigging , face expressions , post-processing effects , ... )
i still can recreate them but of course it can't be as good as original and also because of my inexperience . i would have asked you to seek for a better modder , if there is .

hey i just found it by this https://www.deviantart.com/melanavis/art/Himeno-Sena-from-KoiKake-607568652

if you can fix her, you can google her image for reference.

it seem nobody make model yet
cause it from visual novel that ppl barely know
but i have visual novel community which play left 4 dead almost every day
using weebs character model from several source. some of them from visual novel too
if you can create one
our community woud look foward to your work.

well sorry , main reason is due to technical issues .
but like i said , i can give it a try if you send me the model . it could be .pmx , .obj , .fbx ...

idk how to use 3d program such a bender or other smilliar software but
if you can convert model from koikatsu card
can you do it ?

maybe i can , if you send me the model

could you make Himenso Sena ffrom Koi x shin ai kanojo pls ?

nice

事朱雀院，www
A great job

Te refieres a disfrutar del mod de mi amigo, verdad?

me gusta que no se muestre nada del inventario en el personaje