TV-Series
Description
Oshaki is a female Cocotama, a small apprentice god born from an encyclopedia that belonged to Kokoro's father, Koichi, and was kept in his study. In the anime, Cocotama are tiny apprentice gods born from objects that people cherish, and Oshaki is known as the Book God. Her full name is Shakishaki Shaberi-nushi no Mikoto, and she is referred to in some materials as Shaki-Shaki Talkable Master-no-Mikoto. She makes her first appearance in the fourth episode, where she struggles to come out of her egg. The reason is that the book she was born from had been accidentally torn by Kokoro's older brother, Masato; once the damaged cover was repaired, she was finally able to hatch. After that, she enters into a landlord contract with Kokoro, which allows her to live in the Cocotama House inside Kokoro's room. In the toy line, her egg is blue.

In appearance, Oshaki resembles a light blue chipmunk. One of her distinctive features is her tail, which is shaped like an open book and can be moved at will. The mark on her eggshell underpants is a yellow lightbulb, fitting her reputation as the quick-thinking member of the group. She is very polite and graceful, and she uses a formal style of speech, addressing Kokoro with the honorific san and referring to herself with the polite first-person pronoun watashi.

Her personality is serious, methodical, and hard-working. She is highly knowledgeable, strict about rules, and quick to scold the other Cocotamas when they get too carried away, which makes her the voice of common sense in the household. She is also extremely helpful and is good at coming up with ideas, and she can act as a detective and even a lawyer when a situation calls for it. She has a nature that cannot refuse when someone relies on her, so the other Cocotamas frequently depend on her to read, explain things, and make plans. Soon after her birth, because she was covered in dust, she assigned Luckytama and Melory the job of cleaning and doing chores, showing her exacting standards. One of her recurring comic traits is her singing: her voice is noticeably off-key, and those around her often cover their ears, with Melory being especially bothered by her songs. Oshaki herself is aware of this weakness.

Her motivations are shaped by her role as an apprentice god. Like the other Cocotamas, she is training to become a full-fledged god, so she works hard to be useful to humans and to fulfill her duties properly. Her respect for rules, her diligence, and her desire to be depended upon all drive her actions. She takes pride in being reliable and in using her knowledge to help those around her.

Within the story, Oshaki serves as the brains, organizer, and rule-keeper among the Cocotamas living with Kokoro. Her planning and deductive skills help the group solve problems, recover lost objects, and handle the various incidents that occur around the household. Her relationship with Kokoro is one of a respectful resident; she lives in the Cocotama House under the landlord agreement while Kokoro looks after all the Cocotamas. With her fellow Cocotamas, she balances the energetic and playful natures of characters such as Luckytama and Melory with sensible advice and discipline, though her strictness also leads her to assign them household tasks. She is frequently relied upon by Luckytama and the others, especially when reading or detailed thinking is needed.

Her development across the series is fairly consistent, as she remains the dependable and intelligent member of the group. Episodes focused on her, such as one in which she considers moving out, highlight her responsible nature and her difficulty in refusing when others depend on her. These moments, along with the running gag of her poor singing, give her serious personality a softer and more humorous side. Her defining strengths remain her knowledge, her sharp thinking, and her ability to organize and solve problems.

Her notable abilities center on intelligence rather than physical feats. She is widely read, quick to devise plans, and skilled at investigation, reasoning, and arguing a case. She can also use her own magic phrase, Shakishaki Oshaki no shakkiri kiriri, as Cocotama do when performing their duties. Her movable book-shaped tail and her lightbulb mark visually reflect her identity as a spirit of knowledge and bright ideas.