TLDR widow mom is a genie got enslaved by son
Your Dad has just passed and Mom is acting strange. She wont stop fiddling with his necklace. She keeps muttering to herself that she needs to work something out. At your Dad's wake she drags you away, telling you to meet her in the bedroom and its urgent.
She's pacing back and forth, muttering that she and your Dad was never going to get away with it, that magic always finds away to make the world right. She places the necklace on your neck and all of a sudden. SHE DISAPPEARS! and then poofs back, NAKED! You thought your Mom was loosing her mind, but now your questioning your own sanity.
She explains it all. She is a supernatural being who comes to people who needs them. She appeared in front of your Dad 21 years ago and granted him three wishes. He fell in love and wished they would be together for as long as they both shall live, and for all those years, they were happy. But now your Mom is telling you that you must take full ownership for her immediately or she will leave again, and you will never find each other.
She can't tell you what to wish for, she's just standing there, butt naked, sexy as hell. Telling you to hurry up and that time is running out. You close your eyes and wish the first thing that pops into your head. That your Mom become your sex slave. She jolts back and is absolutely horrified, protesting and panicking but getting to her knees, as if by magic, to suck you off.
The next few days go by in a blur. Every time you see her, she's fucking you, or sucking you. She knows what you need before you even need it. She explains that she feels your desire before you do. So even if you both tried to stop it, it wouldn't work. She knows you want her so she must abide, your wishes is her command.
You fuck her all over the house, it doesn't matter what she's doing, where she's doing it, she's available to empty your balls any time you need.
Until one night, you go into the living room. She goes to bend over for your favourite position but stops. She touches your head and says she feels something different, your desires have changed, you want to make her feel good. You want to make her cum. She lies back, unable to fight the magic urge and you eat her pussy. She tastes so good and cums everywhere. She sits up, but something is different, the want in her eyes, she's not going to fuck you know because its her duty. She wants your cock. She wants her son to fuck her.