Mikuru tried to push Sarah back, but the feeling of her breasts being assaulted like this was so overwhelming that all she ended up doing was leaning back and moaning lewdly while the cleaning girl continued.  "No... Sarah, please..." she managed to beg between moans, but it was clear she was barely even trying to fight back the pleasure at this point.  Already she could feel an orgasm coming, just from the sensation on her breasts.