Remus John Lupin was deathly afraid of spiders. He had so many bigger things to fear, but firstly, he was afraid of spiders. When he was seven or eight, he lifted up a mug in the kitchen cupboard and a spider scurried out of overcrowded depths of cabinet and up his arm. The mug smashed to the floor. When he was nearly eleven, he pulled a coat out of the closet next to the door in his childhood home. After gathering his things and dressing in worn down coat, he shoved one hand into a coat pocket, and put the other on the doorknob. Before he could even step outside, there was a stinging sensation in the covered hand. A spider bite, for sure. When he was in his third year, he was pulling on his gloves for herbology-his second to last favorite class, absentmindedly talking with his friends. He picked up his left glove and shook it out. His dear old friend, the spider, slipped out of it. Supposedly, he made some horrific screeching noise. He doesn't quite remember. He just remember the constant ridicule and laughter from his friends; especially Sirius.
Sirius Orion Black was horrified of the dark. He has a very distinct memory of getting shouted out by his Father for leaving a candle burning while he was asleep. He was about ten at the time. It happened several times after that. Into his teen years, even. Sometimes he'd be certain he'd left it going while he was asleep, and it would be blown out before it melted all the way down. He never knew for sure who was blowing the candles out. Perhaps Regulus. He'd asked his younger brother a few times. Regulus denied it every time. In his second year, James blew out the last two candles that were going, plunging the tight dorm into darkness. He didn't feel as frightened when his friends were around, and no one cared that much when he left his bed curtains open; this was like any other night, but it felt different. He felt so uncomfortable, and the moonlight was so dreadful and dim. James didn't seem to mind when his best mate had asked if he could stay with him. Or, when Remus had woken up and joined them.
Remus "Moony" Lupin was deathly afraid of heights. His friends always tried to drag him out of the library and onto the Quidditch pitch to teach him how to fly a broom. He had zero athletic ability, anyway. It wasn't like he was going to play. When he was in his first year, they were required to take a short introduction to flying. After smacking himself in his sore shoulder multiple times with the broomstick handle and climbing tentatively onto it, and immediately feeling unbalanced and swearing off brooms for good. When he was fifteen, his cousin was getting married during the summer in Norway. His Muggle mother, Hope, had always sworn off that "wizarding nonsense" and purchased plane tickets for the Lupin's to fly to the Norwegian countryside and back home. After the plane took off, Remus had pulled his knees up to his face and placed his hands over his ears.
Sirius "Padfoot" Black was horrified of snakes. Perhaps it was all of the Slytherin influence in his world, maybe not. He was scared of them, he wouldn't admit it, but he was. There was an old broom shed behind his home-no, not a home, not really- where they, himself and his brother, stored anything their parents wouldn't allow inside. Regulus had been chasing him down to the shed, they were nine and six at the time; still carefree. Gathering some balls for a makeshift kids game of Quidditch. Sirius flung the door open and slipped inside. As he turned his head, he caught a flash of movement on one of the shelves. Stepping forward for a closer inspection, a long, narrow thing had flopped off the shelf and slithered out the door. A snake. He shouted for Regulus to watch out, whenever anything happened to his little brother on Sirius's watch, his Father would make sure he heard about it. Regulus loved the the thing, though. Something unnerved him about snakes, how constricted their movements were, the narrowed eyes and forked tongues, something. It didn't help that his house was full of them, the honest kind and the metaphorical kind.
Remus Lupin was deathly afraid of himself. When he was a little boy, a monster crept through the window into his room. He doesn't remember exactly what happened, but he remembers all of the pain and screaming. Every month on the full moon, he gets reminded of it. One of his greatest fears was becoming like those werewolves who started forcing themselves to change, and getting stuck in a purgatory-half man, half wolf. He really was a monster, though. If you opened up Newt Scamander's, Fantastic Beasts and Where to Find Them or The Monster Book of Monsters, you'd find him. Highly dangerous, shunned in society. He was never close with his father because of this. His father, Lyall had been an anti-werewolf activist since before he was born. Lyall would do near about anything for his son, really, but he didn't know how to help his son, and Remus never knew how to speak to his dad, either. Remus understood why all of this happened, his family who knew was embarrassed by him, if any future employer were to perform a background check on him, they'd see that he was monster, so he better keep his grades up as high as he can. Quite frankly, anyone could at least guess he was a monster, as his face and body were littered with scars. It was the biggest shock in the world when his best friends, his only friends, had accepted him. Not just accepted him, but wanted to help him. The shock got even bigger when Sirius had accepted his invitation to go on a date with him.
Sirius Black was horrified of his parents. They loved to torment him more than most anything. He was their screw up son, their gay son, their punching bag son, their Gryffindor son. He was screamed at, slapped and thrown to the ground every summer. He never shed a tear. In the beginning, Regulus was there to lend a hand and fix up his hands and back, but by the time he started at Hogwarts, he stopped helping. Regulus never wanted this to happen to him. He took the easy path, he wasn't really happy in Slytherin, but he didn't end up on the cold marble, bleeding. The break between fourth and fifth year was the worst, for Sirius. He had recently started seeing Remus, he hadn't been happier in a long while. His second night back with his parents, was when Regulus casually mentioned it. The Blacks were outraged. Sirius had never been this upset. No one was allowed to talk about Remus like that. This was the time he fought back. His Father fought back harder. Sirius knew he wouldn't win this time and fled the first chance he got. He stumbled to the fireplace and reached out for a hand of floo powder and shouted for James Potter's house. He cried this time.
Remus and Sirius were more afraid of hurting each other than anything else. Remus didn't want to get close to anybody. He could tear them apart in seconds. That could be Sirius, or James, or Peter. He was an ankle weight in Sirius' life. Sirius was so worried about Remus. If anyone found, or someone slipped up for just the slightest moment, his life could be put on the line. Or if Remus got away during a full moon… There are creatures bigger than his Moony out there. That would be on him.
But they loved each other.
And they managed.