A/N: After Sirius left Grimmauld Place and broke Regulus, Y/n was there to pick up the pieces
3rd POV:
Y/n watched the boy beside her lightly snoring in his sleep. It had been the first time in weeks since Regulus was able to get real sleep. Y/n and Regulus had just entered their fifth year when Sirius had left their home. Regulus wouldn't say this out loud, but his brother was his savior, keeping him sane in that house.
Now that Sirius had left, Y/n stepped in. She would sneak in and comfort Regulus, whether it be singing to him, giving a shoulder to lean on or just being there. Regulus believed love was for the weak, but that changed once he met Y/n. They met at the Slytherin Quidditch tryouts where the captain refused to let her on a broom, but that didn't stop her. She was able to transfigure a pile of sticks into a broomstick. She outflew everyone that day, earning her spot as chaser.
It was understatement to say she was furious at Sirius, words couldn't describe it.
Y/n pushed the curls that covered hair, and she couldn't help but let out a small sigh. She had never seen him like this. Yes there were times where he bad days and he would cuddle with her and the pain would go away, but there were no amount of cuddles that could fix this.
Sirius didn't know his brother was hurting. In that moment, he just cared about himself. He had left that cruel home and was finally free, being able to live out the rest of his teenage years with his best friend, James Potter.
Regulus was envious of James. Regulus hated him. Though the two never had really talked, Regulus saw how happy Sirius was with James, the two 6th years sharing a brotherly bond. Even when they were children, Regulus and Sirius weren't that close. James had replaced Regulus.
Even through his hard tough exterior, Regulus was as soft as they come, the only person who saw that was Y/n. She always told him bottling his emotions like he did was unhealthy and it was okay to show weaknesses. He showed weaknesses to Y/n.
Y/n wiped the sweat that had settled on his forehead, he had been wearing long sleeves and sweatshirts to cover up the dark mark on his arm, causing him to become hotter.
They really didn't have anyone else, they had the same friend group but they could never confide in them like the way they do with each other. Y/n and Regulus held the other's deepest darkest secrets.
Slowly Y/n was able to slide off the bed without waking Regulus and put on her slippers and grabbed one of Regulus jumpers and tucked her wand in the band of her shorts and walked out of their prefect dorms heading for the Gryffindor Tower. She had planned his confrontation for weeks, cornering Sirius asking why he did it. Y/n knew if she told Regulus about this endeavor, she wouldn't hear the last of it.
"Let me in." She ordered the painting.
"Young lady, you need a password." The painting replied in the same tone.
"Bludger." She stated, they always made their passwords easy. Once she walked in, she saw Sirius and his group of friends and a few girls sitting on the couches and chairs.
"You!" She shouted at Sirius stomping towards already having her wand out.
"Hey!" James stood up and grabbed his wand ready to defend his friend.
"Bugger out Potter, this doesn't concern you." Y/n spat conjuring worldess magic sending jinxs towards him.
"Do you know what you've done." Y/n pushed Sirius up against a wall, her wand pushing up into his throat.
"I-I don't," Sirius wheezed out.
"You broke him when you left, you didn't think what he would go through. You only cared about yourself." Y/n growled pushing her wand up further.
"I had to leave." Sirius tried to help himself.
"He had to leave too, no one deserves to stay in that house, do you even know what happened to him once he left, do you!" Y/n shouted.
"They didn't." Sirius paled.
"They did, I couldn't let him into the kitchen by himself thinking he would scrap it off with a knife." Y/n whispered so no one else could hear.
"Stop!" Remus shouted.
"Sod off, Lupin." Y/n retorted. "I don't know how you're friends with him, he's as bad as the Slytherins he hates."
Before she could hex him, it felt like someone was in her mind. "Expelliarmus." Y/n's wand was send across the room into the hand of Regulus. Hair in all places, bags under his eyes, he must of woken up to see Y/n gone. "C'mere." She obeyed shoving Sirius another time before running up to Regulus. "I'm sorry."
"There is no need." He whispered into her ear before kissing her temple.
"Why?" Regulus looked at Sirius.
"Reg-" Sirius frowned.
"Did you ever think about me?" Regulus cut him off.
"I-" Sirius tried to defend himself but it was no use, he couldn't win this battle.
"You know I would have left with you." Regulus pressing his lips in a straight line. "I would you follow you to the ends of the earth."
"Regulus you have to understand..." Sirius pleaded.
"But you wouldn't do that for me." He cut Sirius off again. "Come Y/n/n, let's go back to bed." He started to walk out of the Gryffindor common room.
"You were his savior, the light in the tunnel, but you replaced him." Y/n spoke darting her eyes towards James. "Looks like I replaced you, I'm the savior." And with that Y/n left.
He didn't know it at the time, that was the last time he spoke to either of them.
***
"Padfoot, who is that?" Harry Potter asked while they were in the living room of Grimmauld Place almost 20 years later.
"That was my brother Regulus and my sister-in-law Y/n." Sirius answered giving a sad smile
"Was?" Harry raised an eyebrow.
"Regulus was my younger brother. I had left here when I was 16 and he was 15. I left him here in this god forsaken house. Y/n was furious with me, stormed into the Gryffindor common room one night cornering me. If it wasn't for Regulus, she may have killed me right there." Sirius said. "I deserved it though, they didn't speak to me the rest of the time we were at Hogwarts, I tried but they wouldn't give in. A year after I left Hogwarts, Kreacher had found me and gave me a note, Regulus and Y/n died trying to go against the dark lord. Y/n became a death eater for Regulus."
"Do you miss them?" Harry asked.
"I wouldn't admit it out loud, but yes. I regretted every decision I made that year and I wished I could have taken Regulus with me that night, and they would be here, happily married and having there own family." Sirius sighed.
———