Nakaiko's manga / #Adventure(16)

Love it. Insanely smart guy in a world of nothing bringing it back to a modern age doing everything to get there as fast as possible. Though having the knowledge, he is still one man and needs others to help in in bringing about his ideas for his goals.

It's a mix of isekai and otome game. You know the drill. Just a normal guy somehow gets into another world, gets power, and gets chicks.