This is a parody of a page from a Manga by the artist aoki_kanji "Manga is by 青木幹治 / Kanji Aoki, published in 漫画ばんがいち 2006年 11月号 / Manga Bangaichi 2006/11. The title is “お姉ちゃんの手を取って”, “Take Oneechan’s Hand”. He is a regular contributor to Bangaichi, but seems yet to have released a compilation." From http://www.sankakucomplex.com/2008/05/12/oppai%E2%80%A6/