I was on my computer last night and I happened to be thinking of something very useful to me that I will call X. I was hungry so I added 15 to it like this:
$15 + X$
That did the trick. Later on, I wanted to go for a walk. I added 14 to it:
$X + 14$
And enjoyed my walk very much. It made me think of my childhood home. There were gooseberry, raspberry, and red currant bushes in the backyard. My backyard is too small for that. Obviously, the solution was:
$X + 13$
When I arrived back home, those memories made me feel lonely. Once again, X to the rescue:
$12 + X$
It had been an eventful evening. I had trouble sleeping. Instead of counting sheep, I decided to try a more complicated sum. I tried adding:
$11 + X + 13$
But I fell asleep before I got the answer.
I had the strangest dream. I dreamt that
$10 + X$
is male but
$X + 10$
is female. When I woke up, it I found it was true.
What is X?