I was on my way to hang out with some friends when my stepmom called and asked me to swing by my step grandmas house to check on her. I knocked on her door but she didn't answer. I knew where she kept the spare key so I let myself in. I went downstairs and found her getting dressed. For some reason it turned me on. She saw me looking at her and scolded me for jerking off on her. She noticed me checking her out and asked me if I like what I see. Of course I did. She pulled her bra down a little to show me her tan lines and I reached up and grabbed her tit. To my surprise she didn't seem to mind. I pulled grandma into her bedroom where she stripped naked. My cock was aching to get out and into her sweet pussy. But it was quite awhile since she had been fucked by anyone so she wanted to play first. Then I slid my cock into her wet pussy and banged the fuck out of her. Her tits were flopping as I was stroking into her. I finally busted a nut all over those big floppy tits of hers.