Teaching Stepson Anatomy

My soon to be stepson seemed a bit stressed, so I asked him what is up? It turns out he is having a hard time in two subjects, philosophy and biology. I know absolutely nothing about philosophy, but I am ok at biology. He says specifically he needs help with anatomy. Well, I can absolutely help him with that! Things start a little awkwardly as attention shifts to my breasts. I explain to him that there are all kinds of boobs, natural ones like mine, or implants. He wants to know more so I take my dress off and spread my legs. We go over the different female parts and I ask him if he has any questions? I can't help but notice how hard he is getting, and I wonder if he looks anything like my boyfriend. Once his cock is out I can see how grown he is and I want to show him more. I am getting hornier, and he can't resist taking a taste of my pussy. Sliding a finger in I cum on his hand as he finger fucks me. So good but I realize my boyfriend will be coming home soon. I plan on tutoring my