Project Luster

The Ultimate weapon worked exactly as intended, right up until it wiped out almost every man on the planet. The creatures left behind adapted by taking on humanoid forms so they could breed with whatever's left of humanity, though not all of them are on board with that arrangement, which is where the fighting starts.

Lysandre's weapon is the reason the world looks like this now, and the handful of surviving men are the reason anyone still cares. Project Luster runs that setup as a straight monster-catching parody: humanoid monster girls in place of the usual roster, a male protagonist who's suddenly very in demand, and no shortage of creatures unhappy about their new biology.

You play the trainer role straight, moving between towns, running turn-based fights, and building up a harem of monster girls you've caught rather than punched into submission. The town of Sapphiron has had its interiors reworked to feel properly lived-in, with clutter and decoration that make it feel less like a placeholder map and more like somewhere people actually live, which is more effort than most games in this genre bother with.