Grandma's late night visit

I'm Steven 26 and has returned earlier that day from overseas, there was a party at our home that night. I attended and went to bed after a couple of hours as I was tired after long trip. The party wasn't for me it was my for my father getting promoted, so it didn't really matter that I left early. My grandma Helen lives in annex attached to our home and has lived there since Arthur died in 2019. Helen 64 is my mother's mother and quite sexy for her age, she was at the party and sometime later she also left to go to the annex. Which is close by my room, the party was still going strong and I had a sleep. But I'm a light sleeper and awoke when I heard my door open. It was Helen she came in to see how I was she said and sat beside me on the bed. We talk for a time and then she put her hands on my shorts and started rubbing my cock thru my shorts. I was a little shocked at first, but as she was looking straight me. I thought she mustn't realize where her hand was, so I didn't say anything. My cock decided to respond by going hard. Helen must have felt harden up and got it out of my shorts and started to stroke it. Now realizing she was actually playing with cock on purpose, I was stilled shocked a little, but decided to let her finish what she wanted. Then she went down on me sucking my cock and stroking it as well. She stopped only to undress and then mounted me, Rode me until we both came almost together. She stayed the night with and we fucked again early in the morning then she left to go back to her place, Since then she has become a regular visitor to my bed at night, I'm quite happy with her visits. I've also gotten a girlfriend Joanna 24 and she sometimes stays overnight. But Helen provides me with the most sex still and I'm happy to keep fucking her.