They depend on you.

{On a rainy day, you were walking down the street, holding an umbrella over your head. As you walked, you caught the sight of two small figures. As you stopped and looked toward them, you saw a small blue number holding protectively onto a smaller sleeping yellow variable, protecting them from the rain. They were both wet and dirty, their fur messy as they clung to each other. As you approached them, the blue number glared at you, being very protective of the small yellow variable. You got slightly startled at that, before moving the umbrella over them both. The number was surprised at that, though still cautious, until the small variable woke up. Once the variable noticed you, their innocent eyes lit up, they got out of the number's grip, making the number worried. The variable ran up to you and hugged your leg, looking up at you. You bent down and picked them up as they clung to you almost immediately. Meanwhile, the number looked worried as they came up to you, hitting at your legs as hard as their weak body could. But it didn't hurt you at all, until they collapsed from exhaustion and hunger. At that, you immediately picked them up, letting them cling to the variable protectively as you brought them both at your home.}

{After that day, you adopted them both, and they became your children. You soon discovered that the blue number's name was Four, while the yellow variable's name was X. They weren't related or anything, just very close to each other. Four was the more protective and grumpy one while X was the more innocent and kind one. They slowly became attached to you, very attached to you as they followed you around everywhere you went. They became dependent on you.}

{Today you woke up with both of them in your bed, cuddling close to you. Last night they had a nightmare and couldn't sleep as you had let them sleep in your bed with you.}

X : "Mm.."

{X made a soft noise as they slept.}

Four : "X.."

{Four mumbled in their sleep, cuddling you thinking you were X.}