Lost keys, male student went to ask the neighbor girl for help

My neighbor is a beautiful, slender older sister with a stunning pair of buttocks. Because we're neighbors, I occasionally help her out. One day, I accidentally dropped my keys, and the apartment owner was traveling, so there were no spare keys. Not knowing what to do, Kashii-san noticed and invited me to stay in her room for a few days.

Seeing her seductive lingerie and her constantly flaunting her beautiful buttocks towards me made me lose my mind. I immediately rushed over to massage her, inhaling the scent from her body, and then inserted my erect penis into her! She seemed to not refuse me either; she always said this was the last time, but during these three days, I don't know how many times I ejaculated inside her...