Yandere! Younger Brother & Reader (Older Sister)

The incident

Sorry guys I haven't updated in awhile :c. I think I'm getting a bit sick, but don't worry that won't stop me from writing! Warning: this chapter will most likely make you cry!

Not every day would be as good as the others. Everyone had to know that.
You played inside with Haku. A game of tug-a-war is hard to win especially against your furry friend. You scowled at your dog and he growled back. You both pulled furiously at the ends of the ropes.
"You shall not win, Haku!" You pulled with all you might; your hands slipped over each other.
You flew back, but before you could slam back into the table behind you, Saiyo came to your rescue. He dived into your back.
"Woah!" You lost your balance and fell back onto your lump of a brother.You both piled onto the floor together.
"Sorry!" You slowly pulled yourself off your brother.
"N-n-noo! It's my fault for getting in your way!" Saiyo's nose bled slightly as he stared at your partially ripped shirt.
"Eh?" You glanced down at yourself, and noticed too.
"Don't look!"
He covered his face and blanketed himself with his arms closed around himself. Red as a tomato (if you read hetalia fanfics you must know what I mean the most ;) ) , you closed your eyes and legs dashed away. Haku followed along, like the obedient dog he was.
~~~~ 2 hours later~~~~
It was a little past mid afternoon. You were doing some sewing like your school taught you to do every now and then. The doorbell rang and you rushed to it.
Earlier, you had asked your friends if they would like to get something to eat soon. Of course any chance was the best, as long as you got to stuff your face.
You flung the door open prepared to leave, but saw no friends of yours. A tall, thick man proceeded through your doorway. You stepped backwards; the man walked in.
"Can I hel--", a base ball bat swung at your stomach; hitting your arm in the process.
You dropped to the ground. Pain surged through both your arm and stomach. You clutched your wounds tightly. Fragments of tears rained off your cheeks and onto the floor.
The man's gaze swept around the house as if searching for something. He lifted a sack over his shoulder.
"Theft?" You thought to yourself.
"I have to warn the rest of the family!"
You shifted your head upwards, and sounded like a rusty alarm.
"Get out you guys!"
Footsteps and pawsteps, charged down the stairs. Your parents and dog appeared in the knick of time. They confronted the enemy.
"Dad, Mom, Haku!" You smiled.
"Hold on there, (Y/N)!" Your father assured you.
The bat flew your way again, and slammed you back into a corner. You closed one eye. Blood spilled before you, not only was it yours but the others had also spurted across your face.
You watched helplessly as they fell one by one. You saw the man's bat beat your dog to a pulp.
Haku wobbled your way. You listened lightly to him. He whimpered his last goodbyes, and collasped to your side; his blood drained down onto you.
You thought you could make out what he said to you.
"I had fun", you figured.
You sobbed. Hugging your best friend, you felt a heavy weight droop on you.
You heard extra footsteps. Saiyo? No, there's no way! Your eyes flinched to the man. Saiyo stood behind him with some type of kitchen utensil?
The man smirked looking down upon you, not noticing your brother. Saiyo pulled his hands to his side, and threw the sharp glinting utensil into the back of the man. He drove it through him till he fainted to the floor.
Your brother rushed to your side. Your eyes widened as he embraced (hugging way! We haven't made in that far yet) you tightly. He whispered softly in your ear with a quivering voice.
"I'm sorry I couldn't make it in time for the others."