My black, very chubby mother in law of 68 years came to live with us when she retired because she couldn't affort the rent of her own home again.
I'm 35 and horny through the day, it never seems to end.

My mother in law knows it because we're alone often and she regularly caught me wanking on my bed. She seemed to have a nose for it because every time I did she walked in and didn't respect my privacy.
The problem often was, at the moment she walked in, I was too horny to stop and often she stayed and watched me untill I came. Without a word then she disappeared. After a few times I didn'nt bother her watching, on the contrary, I thought it was pretty exciting if she came watching at me.

Untill 7 month ago, she came into my bedroom again, but this time in her bathrobe. She came upon me, removing her bathrobe and I saw she was completly naked under it. She crawled upon me, grabbing my dick and letting herself lowering on it. Without a word, just looking at me , she began to ride me, at first a kind of slow, then faster and faster. She didn't stop when I came, just squeezing her c**t so my horny dick stayed hard and she rode me without stopping, just keeping looking at me with her big black eyes without saying anything. She came so hard I spontaneous filled her up fully again.
Then she just grabbed her nightrobe and disappeared.

Since then she visited me about three or four times a month, it just happen without we spoke to each other about it.
It's part of the ever horny tension between the two of us, she just wait untill we're alone and I'm alone in my bed, come in, dropping her nightrobe, ride me intensive and disappeared again.