Rule 2: Never Lend Money to Marui-senpai, you won't get it back.
"Marui-senpai! Where's my thousand yen you owe me?!" Kirihara yelled out to the red haired tensai who was casually sauntering along.
"Hmm?" Marui turned to the approaching junior, "Oh that. Sorry I used the last of my allowance to pay off the hardware store we wrecked when we followed Niou. And I don't get my next allowance until next week."
Kirihara sighed audibly, he had forgotten about that. "Fine, pay me back first thing next week then!"
The next week came and Kirihara still didn't have his thousand yen. So being the impatient person he is, he stormed up to his 'genius' senpai and glared at him. "Where's my yen?!"
Marui glanced at the green eyed second-year confused before realization dawned on him. "Ooooh, that. Well my parents made me take my little brothers out yesterday and I bought a few things for myself so I don't have any left. Sorry," he said not sounding very sorry.
"But you told me you'd pay me back this week!" Kirihara fumed. "I better get my yen back next week or I'm telling Yukimura-buchou on you!"
Chuckling slightly Marui jogged back to practice throwing a reply over his shoulder, "Yeah, yeah, next week seaweed-head!"
"Oh, he better pay me back," Kirihara muttered before kicking the ground and turning on his heel to walk away.
By the time next week rolled around Kirihara had gotten so fed up he went to Yukimura-buchou and told him of Marui's yen stealing ways. Yukimura had addressed him with a smile and an "I'll handle it."
Thus, Kirihara was waiting around to see the fruits of his tattling.
The next day Marui came to practice completely out of it and Jackal looked positively mirthful. Bouncing up to Marui happily thinking he was going to get his yen back Kirihara grinned at his senpai, "So Marui-senpai do you have my yen?"
Marui instantly slipped up and missed his serve and spun around, "Huh? What? Noooo. I don't have anything else! Yukimura-buchou! I paid Jackal back okay!" He swatted at the air wildly before taking off in a run.
"Tarundoru!" Sanada yelled to Marui who was making a beeline for the gates.
Kirihara was understandably lost. So there he stayed blinking while trying to process what had just happened. Coming to the conclusion that Yukimura-buchou's methods might have worked a little too well he frowned. He still hasn't gotten his thousand yen back! Glancing to where Yukimura was he debated with himself whether or not to ask if he could get his yen back. But upon seeing Yukimura's content smile he promptly decided that a thousand yen really wasn't worth it.
Extended Ending:
Kirhara dug through his bag trying to find his wallet. He had just finished up an extra training session and was in need of water. So coming across a vending machine Kirihara had stopped and started picking through his bag.
Finally finding it Kirihara let out a small, "Yes!" before opening it. He looked in and only found a small scrap of white paper. Unfolding it he quickly scanned through the kanji. The note read 'Sorry seaweed-head, had to borrow some yen to pay back Jackal. I'll pay you back next month. =p.'
The second-year ace's eye twitched. "Marui-senpai," he muttered darkly clenching his fist while veins popped up on his head. Oh, this was so going in the book.