A mysterious gathering - Demon City (FM Towns) [1993]

I love the style used in CGs from old school PC-98 VNs. I've been wanting to get into them ever since reading 16-bit Sensation. I think the fictional company in the manga(Alcohol soft) is even supposed to be a a reference to Demon City's devs (Cocktail soft).

Oh this is lovely! The dithering on the background is the best, super wonderful sky.