Raw:
https://www.pixiv.net/en/artworks/69586541
https://eh.makinico.moe/g/4214607/c7d10dd10a
Artist: ふいな (fuina / iorifina)
Translation by: owphoenix

Comment from author in Pixiv (translated):
Set before the final battle of the original game. It's my first erotic work, so please forgive any shortcomings.
I'm finally giving form to something I wanted to write back when I first beat the original game, so I'm ignoring the plot developments of later games.