| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Honto no jishin o te ni ireru kokonotsu no suteppu: Chisana koto ni sayu sarenai. | 978-4-8047-6222-7 (4-8047-6222-1) | 2013 |
| Seishinkai ga oshieru aisuru hito to shiawase ni naru 55 no ruru. | 978-4-8047-0452-4 (4-8047-0452-3) | 2011 |