Juunenme, Kikan wo Akirameta Tenisha wa Imasara Shujinkou ni Naru

Ten years after being transported to another world. It was more than enough time to awaken from what at first, felt like an exciting dream in a fantasy world. And on this 10th year Wasa Tooru finally decides to give up searching for a way to return to Japan, after being unsuccessful for so long. It was then that he received a job offer — to be the bodyguard of twins who have knowledge of Earth.