TSUYU
"I fail to understand how this game is supposed to help us improve as heroes," Iida said, staring skeptically as everyone lined up on both sides of the pool.
Kaminari quickly said, "It's uh, for situations where we might need to hold our breath! It's important for us to know our limits."
"Ah, I see! A very good idea, I beg forgiveness for doubting your wisdom."
Kirishima gave the countdown. On three, everyone jumped in, including Izuku, who hit the water in a belly flop with a mighty, wince-inducing slap. Mineta struggled to stay at the bottom, as the spheres on his head tried to drag him up, while Izuku and Kirishima sank like stones. Once everyone settled at the bottom, they sat around and waited, all grinning at each other. After two minutes, Sato tapped out first. The rest of 1-A quickly followed suit, leaving Izuku and Tsuyu at the bottom.
"They've been down there for a while," Kaminari said nervously after some time had passed. "You think they're okay?"
"Tsuyu's a frog, so she's fine. But Izuku… I dunno, man, do you think he's stuck down there?"
"He can literally turn into a boat," Ochako said with a done-with-this expression. "I'm sure he's fine."
After more time passed, Mineta asked irritably, "How much longer is this going to take? I want to head back in with all the girls!"
Sero raised an eyebrow at him. "With how bad you are at holding your breath, I doubt you'd get much of a view."
Mineta sputtered indignantly at the charges while most the guys laughed and most the girls resolved to tie up Mineta the next time they went swimming.
Iida raised his hand and said, "I believe we should go check on them. It is our duty as classmates to ensure their health, and they have remained down there for a concerning amount of time."
"And it'd be great to get back to swimming," Sero pointed out.
Everyone dove back in, only to find that the pool was empty.
"No way, they both jumped in with us, right?"
"How did they sneak out?"
"Have we been staring at an empty pool for half an hour?"
"And which one of them won?"
Meanwhile, in the men's restroom on the third floor…
Tsuyu wriggled her way through the u-bend and out the toilet. In the stall next to her, Izuku burst through the plumbing, shattering the toilet into a million pieces.
"Do I even want to know why the pool's circulation system connects to the bathrooms?" Tsuyu asked with a shudder.
"Power Loader is not a good plumber," Izuku replied as he picked ceramic shards out of his hair. "Should we go back downstairs and inform everyone that the game is over?"
Tsuyu thought it over. "Nah, I'm sure they noticed we got sucked into that drain. Now, if you'll excuse me, I need a shower. With all the soap."
489
Don't worry, it's just a Snicker's bar.