Sakura's line is weird to translate -- it actually means something closer to "forgive me" or "take pity' or something but in a sexual context I'm not sure if those are necessarily appropriate. Maybe the take pity one. Someone with a better knowledge of Japanese, maybe brush this up a bit?
Given the context of Shizune saying "shimaru," which either means "to close" or "to constrict," I strongly suspect this is futa, since we can't see anything, the most I'm going to do is remove the "yuri" tag.