This is a picture book for babies. It's a picture book where many animals play peek-a-boo. What's on the last page...? The letters are very large, so even young children can read it. The illustrations are also in full color on every page. The paper used for the pages is not ordinary paper, but thick cardboard, so it's easy to open. Plus, the number of pages is small, so you can read it quickly in a short amount of time and feel satisfied. Furthermore, the spine is thin, so it doesn't take up much space even when stored on a bookshelf, and it fits neatly into the bookshelf.