What a strangely abrupt ending-- if that "END" hadn't been there I'd have sworn there was a page or two missing. All of this author's other works have some kind of closure, weird.
Nagashiro Rouge's works have always been kind of a balancing act between thoughtful sci-fi and weird porn, but this one's definitely more on the "weird porn" end of the scale. At least the two of them seem happy together, in their own... aggressive... way.
... Either the last page has a coloring error (Senpai's shirt is supposed to be all-white, specifically), or this scene takes place on a different day where Senpai decided to wear her coat over the white shirt.