My stepsister made me cum in her Batman panties before she leaves for school

My naughty stepsister barges into my bedroom and tells me she wants me to cum in her Batman panties before she leaves for school. I thought she was joking, so imagine how surprised I was when she grabbed my cock and started giving me a handjob. My stepsister gave me a handjob and rubbed my cock on her shaved pussy until I cum in her Batman panties.