Four years ago
"Why are you all following me home?" Haru asked the three boys as they climbed the steps to her house.
"Rin has never seen where you live, Haru." Makoto said to Haru.
"I was curious in what kind of home you live in, Nanase." Rin said, grinning.
"I really wanted to come to your house again, Haru-chan." Nagisa remarked.
Haru sighed as they reached the top of the stairs. "Whatever." She said in monotone. "Just don't mess with anything."
As soon as they all reached the door, it immediately slid open.
"Welcome home, Onee-chan!" a six year old girl, with shoulder length violet hair, two strands of her hair were being held by beads, and ocean blue eyes, greeted cheerfully as she leapt onto Haru and wrapped her arms around her waist.
Haru just stood and stared down at the little girl with a blank stare. Makoto and Nagisa chuckled a little while Rin just stood there with a dumbfounded expression.
"I didn't know you had a little sister, Nanase." Rin finally spoke up.
"Actually, she's my cousin." Haru said, turning to look at the other swimmer with a expressionless face. "Her name is Kokoro. She's staying with me for a bit."
Kokoro finally noticed the presence of the other boys.
"Oh, hi, Mako-onii-chan, Nagisa-onii-chan. " Kotoko greeted with a smile.
"Good to see you again, Kokoro-chan." Makoto greeted back, smiling as well.
"Hello, Koko-chan." Nagisa greeted.
"Now, who are you?" Kokoro asked, looking at Rin.
"I'm Matsouka Rin." Rin introduced himself. "Nice to meet you, Kokoro." He said.
"You have a girly name like Mako-onii-chan and Nagisa-onii-chan." Kokoro remarked.
"I know." Rin said, rubbing the back of his head sheepishly. "But, I'm a guy."
"Is there any chance that you're Onee-chan's boyfriend?" Kokoro asked innocently.
"Eh?!" Rin exclaimed, his face turning almost as red as his hair.
"No, Kokoro, that's a shark." Haru said in monotone, pointing at Rin.
"Is that so?" Kokoro questioned.
"What's that suppose to mean?!" Rin yelled.
"They're at it again." Nagisa remarked.
"They both get along so well." Makoto said, chuckling softly.
"Well, come in, come in." Kokoro said as she grabbed Rin's hand and dragged him inside the house. "Make yourself at home."
"Kokoro, don't cause trouble." Haru scolded as she and the other boys walked in.
"It's okay, she's just energetic." Rin said.
"Rin-kun is right!" Kokoro stated, sticking her tongue out at her cousin.
"Kokoro, don't call him Rin-kun." Haru scolded again. "It sounds weird."
"What should I call him, then?" Kokoro questioned as she put her finger to her chin and thought for a moment. "Oh! I know!" She looked up at Rin. "Onii-chan!" She said cutely, smiling widely. "Who knows, you might become my real Onii-chan someday." She remarked.
That remark caused Rin to blush heavily.
"What are you going on about, Kokoro?!" Haru exclaimed, a scowl on her face as she looked down at the girl.
