I have no idea why her book's title is in question form. "For friends?" was released during Comiket 76 along with another illustration doujinshi, Mizutama. Mizutama had too many two page spreads with too few pages, so I went with this one.
My attraction to Chisato Naruse's art work was re-kindled this past summer, when I finally bought her commercial art book Fabriese. After a quick search I found her doujin circle, Tanpopo-ya and was able to check out her releases. "For friends?" is 20 pages, but only if you include the covers. I notice that Chisato Naruse also includes the covers in her count and has it listed as 20 pages on her website.