- Sam was born in the 2010's, Iris was born in the 1980's, Milo was born in the 1970's, and Lucille was born in the 1850's. Due to all being born from different eras, they confuse each other sometimes.
- None of them can age physically nor mentally.
- They all hang out together on a daily basis.
Sam Williams
- He died when he was 13.
- His mother, Karen, abandoned him when he was 8, right after his father Johnny was killed by Sally. Sam was then left at an orphanage. He spent three years there until Sally's mom and stepdad took him home with them.
- With Sally gone, her parents saw Sam as sort of her replacement. While not adopting him, they made him call them "Mom" and "Dad." They sent him to the school Sally would've gone to if she ever went to middle school. They made him go to ballet class as Sally had once done. They even made him sleep in Sally's room and didn't change anything in it, shoving Sam's belongings into the back of the closet. Sam was very lonely, and he felt as though he wasn't seen as his own person. He lived like this for two years.
- After Sam was killed by Sally, he wandered from place to place until he ended up in the Rocky Mountains. That was where he found Odessa, one of Slenderman's proxies, who took him under her wing. She manipulated him into relying on her, and she makes him call her "Mother." She tells him he's like her because, according to what she's told him, she was also betrayed by her family. Sam is scared of her, but he's also scared of leaving her.
- None of the abuse from Odessa that Sam deals with is sexual: it's all emotional and mental, though Odessa won't hesitate to slap him across the face sometimes.
- It took Sam a while for him to open up to Milo and Iris and Lucille, but it was worth it for him in the end, because the first time in years, he had friends.
- He lives with Odessa in her shack, but he's not targeted by Slenderman because Slenderman thinks he's useless.
- Sam was exposed to weapons at a young age, as Johnny had a collection of firearms. He knows a lot about guns.
- Although he's not blood related to Sally and Ben, he still considers them family. He's tried to forgive Sally for killing him, but due to Odessa's manipulation, he's finding it very hard. He also doesn't know how to feel about Ben.
- Sam doesn't know how to feel about Ella. They're on mostly good terms, but Sam is also uncomfortable around her, like he is around her mother.
- He sometimes goes out of his way to help Iris and Milo with their English.
Lucille Stoner
- She died when she was 12.
- Lucille died in a housefire one night in her home in Ireland in the 1850's. When she died, she was wearing a hazy navy blue nightgown and had her ginger hair tied back in a ponytail with a big lavender bow.
- Her eyes are the color of copper.
- She has burns on both her face and hands, as she had been trying to open the door to her bedroom but was burned in the process. The burns on her face are from a piece of burning wood that fell on top of her from the roof. The tips of her hair are also singed. But despite the burns, she ended up dying of smoke inhalation.
- At first, Lucille didn't know she was dead. She tried searching for her family around town, but when people noticed her, all they did was scream and run away. Lucille eventually found where she was buried, and she was absolutely devastated. She traveled around Ireland for several decades until she decided to visit Italy, where she had always wanted to go. That's where she met Milo.
- After becoming friends with Milo, the two decided to go to America. They snuck on a ship bound for there and hid in one of the storage compartments until it docked. From there, they traveled to the Rocky Mountains, where they met Iris and Sam.
- Lucille loves anything made of ribbon. She often collects ribbons and keeps them in a small box.
- Normally, Lucille is very sweet and friendly. She's also very intuitive, and she always trusts her instincts.
- She lives with Iris and Milo in a small abandoned treehouse. They go to visit Sam every day.
- She still misses her family terribly, and she still wonders what happened to them. But Sam and their friends are always there for her.
- Lucille hates nicknames. If you're not Sam, just call her Lucille.
- In true Irish spirit, she has a hatred for the British.
- Before she died, she lived with her family on a small dairy farm. Her favorite animal was a bull she named Orville, whom she loved to cuddle with.
- Comically, it took a while before her friends could decipher her accent.
Hung Iris
- She died when she was 14.
- She was born in a suburban town in Vietnam. Her parents loved her, but they were always working, so she was often looked after by her older sister, whom she was very close to.
- Before middle school, Iris had a relatively happy life. But she got sick often, and it was hard for her to make friends.
- Not long before she died, Iris went through a depressive episode and dyed her hair dark purple. Her parents had a bad reaction to it, and she was grounded for a week. Her sister tried to help Iris remove the dye, but it was permanent.
- After Iris died by suicide, she killed all her bullies out of rage. But once she did, she was overcome with remorse. After haunting her school for a few years, she snuck on a boat to America and then on a plane to Colorado, where she met Sam. Later on, the two met Lucille and Milo.
- Once she had killed all her bullies, Iris became an urban legend at her middle school (Vietnamese middle schools go up to ninth grade). This didn't do anything to ease her guilt for her actions.
- Since Iris is the oldest of her friend group, she often acts as an older sister for all of them. She's also always the one to calm Milo down whenever he gets angry.
- Her English isn't perfect, but she tries her best. Sometimes, she switches to Vietnamese without even knowing it, and her friends have to snap her out of it.
- The noose she used to kill herself is forever stuck around her neck. She's tried to get rid of it countless times, but it never works. It really bums her out.
- Iris is chubby, which was one of the reasons she was bullied.
- When she cries, black liquid pours from her eyes. Before she died, her eyes were brown, but they turned red when she came back as a vengeful spirit.
- Her favorite color is yellow.
- Iris is a devout Buddhist. Despite feeling remorse for her actions of killing her bullies, she deep down knows that, according to her beliefs, she's innocent because the bullies had it coming.
- She resents her parents for not doing enough to help her when she needed them most, but she still misses them. She also misses her sister dearly.
Milo the Electrocuted
- He died when he was 10.
- Milo was born a sociopath. It's very difficult for him to form emotional attachments, and during his life, the only person he cared about was his mother, whom he was close to. He never made any friends, either, and he preferred books to people.
- He grew up in Aviano, Italy. His English isn't very good, and it's often hard for his friends to understand him because of his thick accent. Because of this, he has to speak slowly, which annoys him.
- From when he was a toddler, Milo was often bullied by his older brother, Dominic, who was five years older than him. Milo thought of him as a "violent, stone-headed imbecile." They fought constantly, and Dominic sometimes ripped up Milo's books out of pure sadism. Because it was the 70's and 80's, their parents, especially their dad, thought they were just being kids, even though Milo was clearly his mother's favorite.
- Milo loved playing in the rain. One day, when he was 10, he was out playing in the puddles again when Dominic and his friends ambushed him. They dragged Milo to a nearby landfill and tossed him into a ditch full of electric wires. They thought he was just going to get a little shock, but all the electric currents, activated by the rain, ended up killing him.
- After Milo died, he came back as a vengeful spirit and killed Dominic and his friends off one by one. He appeared to them on rainy days and hunted them down.
- His glasses are forever cracked and lopsided.
- Milo is often nicknamed "Georgie" by Sam, which he doesn't understand but hates anyways. The reason behind his nickname is his yellow raincoat and boots, and the fact that he died in a rainstorm.
- In reality, he's fond of his friends, but he hates admitting it.
- Apart from the typical ghost powers such as levitation, telekinesis, and passing through walls, Milo can also control electricity.
- He sometimes helps Iris and Lucille do their hair.
- He stills enjoys reading and will sometimes even kill people just to steal their books. Due to being a sociopath, he doesn't care about ending the lives of others.
- Around Milo's neck is an electric chord that wrapped around him when he died. The clothes he wears under his raincoat are also bloody.
- He has an awful temper and will often go on full-on rants in Italian. Because they don't know what he's saying, his friends hardly ever know whether or not to take him seriously.