Ryll, since you read so many manga:

is there any good stuff where isekai inhabitants come into a our real world, and it's a serious, grounded story, not your typical shallow harem moe bs? Like GATE, except better. Anything?

Also, any serious stories where a male adult hero (no child face or such bs) gets into a relationship with a hot monster girl from an isekai? Not an ecchi manga (not predominantly, anyway).

thx