I read the beginning of this a few years ago, but I can't find it now that I want to pick it up again.

The premise was a typical protagonist summoned to a fantasy world (similar to Zero no Tsukaima), but with a twist. The protagonist was an older, male college student/graduate and when he is summoned he is put in the body of a young, frail-looking, white-haired girl. I remember that this wasn't played for laughs and it was all treated pretty seriously.

I think the protagonist also may have been a history major of some kind, because he was super analytical about the situation at the beginning. Also, the guy who summoned him basically created the young female body based on his idea of the "ideal" body. Again, this wasn't played for laughs and it wasn't really treated as ecchi.

Please help me find this. There was some really great world building in the story and I was so happy to find a summoned to another world light novel that wasn't focused on comedy or romance. I'd love to be able to read it properly this time.

Cynicism at its best.