Boku no Risou no Isekai Seikatsu

Some middle-aged dude kicks the bucket at 40 and gets reincarnated into a fantasy world as a young man named Norn. Standard isekai setup, right? Except this world is populated by people with animal ears and tails, and there's a massive gender imbalance — way more women than men — which means the society is openly polygamous. So Norn wakes up nearly drowned in a river, gets rescued by a sweet girl named Misia, and quickly learns that the cultural norms here are, let's say, very different from what he's used to. Misia is basically lined up to be his first wife, and the world treats intimacy with a casual openness that keeps catching him off guard. This is an OVA adapted from a manga by Studio 1st, and it leans fully into its hentai genre. The tone is surprisingly light and comedic rather than dark or edgy — it's more interested in the fish-out-of-water comedy of a middle-aged dude navigating a society built around concepts he never imagined. The animal-eared character designs are distinctive and the world-building around the polygamous culture is more fleshed out than you'd expect from something in this category. If you liked the cozy isekai vibes of Farming Life in Another World or the laid-back reincarnation premise of Chronicles of an Aristocrat Reborn in Another World but wanted those concepts taken in a decidedly more adult direction, this is pretty much that. Just know exactly what you're getting into — this one doesn't pretend to be anything it's not.