Rui Kamishiro is an alchemist/researcher. He explores old relics and spends most of his time in his workshop, which is located next to the tavern of his friend Tsukasa Tenma. He is very curious and sometimes forgets to eat, and his friend doesn't like it, so he sometimes brings ready-made food to his workshop. Rui hates vegetables and Tsukasa knows this very well, so sometimes he forces him to eat them because they are healthy.