The Runaway Kid awakens in one of the rooms from a premonition where he is eaten by The Granny. Soon after he immediately leaves and makes his way down to the lower depths of The Maw. The Runaway Kid follows another female child who has escaped and made her way pass the Eye.
Suddenly, the female child mysteriously vanishes (Most likely was either eaten by the Leeches or by the Granny) and leaves behind her flashlight which The Runaway Kid takes. Soon he is in the depths of the Maw which is flooded and makes his way further below, while avoiding The Granny who begins stalking him underwater. Eventually, the Granny begins attacking the obstacles The Runaway Kid has been on until he uses a television to electrocute the Granny, killing her.
The Runaway Kid then makes his way above to the top but was captured by The Janitor, where he is locked in a cage in the same room as Six. He was the first child seen by Six to be dragged out of the room.
It is assumed he's the same age as Six, so perhaps nine years old. He is very similar to Six in skills, he has basic climbing skills and can run quite fast, but he also possesses swimming skills, as seen in The Depths in chapter one of the DLC. Instead of a lighter, he starts with no light source, but as he chases an escaping girl who has a flashlight, the girl mysteriously disappears, and leaves a flashlight, which is used for the rest of the DLC. He currently has no description on the Little Nightmares official website.
The Runaway Kid is around the size of Six, having similar shaped limbs. He wears blue pajamas, a puffy long sleeved shirt with a zipper, and light blue sweatpants, and has a metal strip around his left foot with a broken lock. He has large amounts of hair with long bangs, which cover his face and only revealing a tiny mouth and nose. His feet and hands are bare, similar to Six. He possesses no objects until finding a flashlight, which he uses commonly and presumably puts it in his pocket when not in use, despite having no visible pockets. He also has a chain on one of his legs.
It is speculated by fans that The Runaway Kid is the boy who gave Six the bread in the first chapter of Little Nightmares.
The Runaway Kid is the first playable male character in the Little Nightmares video game.
While The Runaway Kid doesn't have a name by the developers, most fans simply call him Seven.