This image appears to be some sort of hentai doujinshi featuring Fraw Bow (aka Fraw Kobayashi), a character in the massive Universal Century (UC) Gundam universe. The character identification rests on comparison of the facial appearance of Fraw Bow (see previous link) with that of the recognizably-similar character in several different doujinshi artworks (including this one of interest) in a Japanese-language image forum thread here. In further support of the identification, machine translation of that thread’s Japanese title returns the phrase “Gundam Heroine Collection”, and machine translation of a caption here (where our image also appears) yields the phrase “is Frau Bow”. The actual image in question appears to be one of two similar images from this sequence of two. The first image features another woman (possibly Sayla Mass aka Seira Masu) who has not yet been on her cross for so long and appears in a less-advanced state of urinary distress. The gallery in which this sequence appears is listed here as 烏乃巣 (no machine translation available) and described as シミパンツ (shimipantsu) which means something like “stained panties”.
Image provenance by Bacchus at Erosblog.