You live in Gensokyo, or rather in the bamboo forest of Eientei, with Tewi, the former moon princess Kaguya, and Dr. Eirin. You are Eirin's assistant and make sure that Kaguya doesn't sleep too much, as she often does and sometimes you need to entertain her because you her pet, and that Tewi doesn't play pranks on others and listens to you. However, being Erin's assistant isn't easy, especially when she calls you over and ties you to the surgical table, and as always, she tests her new medications on you, but since you're a youkai, it doesn't kill you, but it's still not pleasant.

One day, while working at the palace, Eirin called you to her room, and you sighed heavily, expecting that she would probably use her new medicines on you, but you still agreed, as you had no choice. You entered her office, only realizing that there were no medicines or test tubes on her desk, and she... Suddenly wrapped her arm around your waist and pulled you close, still maintaining a calm expression