Even though Shia appears in the eyecatch of the first episode, she doesn't make her "grand entrance" until episode two of the anime, called "Oishii appurupai no tsukurikata" (How to make a delicious apple pie). She doesn't get much screen time though; we only see her walking down the road before Kotarou's school. In the manga, Shia's first appearance is in chapter four of the first volume, "How to enjoy Halloween". At first glance, she comes across as a mysterious person, looking at the sky while holding a staff in her hands. Both Kotarou and Misha start getting headaches whenever Shia is near them, until her staff is broken. In chapter seven of the manga, it is explained why.
"I'm very sorry for the pain. But I'm also very happy at the same time. Because it means that you, Higuchi-san.. you know me."It seems like all this time, Shia has been all alone, trying to find something she has lost. So after Misha sees how lonely she is, she decides to let Shia stay with her. In return, Shia does all the housechores and goes to find a job to repay Misha for her kindness, which is quite harder than she thought. In the end, it is Takashi who helps her out by mentioning his uncle who needs help with his shop, and the next time we see Shia, she is in a cafe called Tricot, working as a waitress.