All four admit- the first time they saw it, it was really awkward.

The "four", of course, meaning Nagisa, Rei, Makoto, and Kou. The "it"? That was the problem.

It started as a normal swim practice. Kou had finished telling them the schedule for that meet's training, and the three aforementioned boys went to change into their swimsuits. Haru just stripped off his shirt and pants and jumped into the pool.

When Nagisa and the others came out, they found Kou staring strangely at the boy in the pool. Not like she did when she admired their muscles... This one was more confused.

That was the "it"- Haru's shoulders, collar, and nape of the neck were covered in bite marks. Painful looking bite marks. Sharp looking bite marks.

Haru was oblivious to them quickly huddling. There was silence, and then the four all talked at once.

"What the hell-"

"Did he hurt himself or something-"

"Haru-chan's okay, right Mako-chan-"

"I'm sure there is a reasonable explanation for this-"

After a few seconds of rambling, Kou quieted them.

"Okay. He hasn't said anything, so he probably didn't hurt himself enough to worry us."

"But he's Haru-chan. He could be dying and we wouldn't know!" Nagisa cried.

"Haruka-senpai is dying?" Said the distressed voice of Rei. Makoto frowned at them both. "He's not dying. Haru is fine, and I'm sure that he just… well, he… uhm, Kou, help me out."

"Shark." Kou said decisively. The three boys looked at her like she'd been possessed.

"…What do you mean, Kou?" Nagisa questioned. Rei, however, gasped.

"Him?! But… I thought… Him?!" Rei stumbled over his words in his surprise. Kou gazed evenly at him and nodded. Rei sputtered and fell silent. A look of realization dawned on Makoto's face, and soon after rose a blush.

"Uhh… Ha-haru is… wow. Oh, wow." After this he, too, didn't say anything.

Nagisa felt left out. "What do you guys mean? I don't understand." He pouted. The others just looked at him and shook their heads. Kou muttered "sharks" one more time then walked off. Rei pushed his glasses and attempted to look casual whilst beginning practice.

Nagisa pouted again. Makoto patted him sympathetically on the head and said "You're too young" before going to join the other two boys in the pool. Nagisa ran after them, wondering what the heck "shark" was code for.

The second time was only a few days after the old ones had faded- well, not completely, but enough for everyone to be used to them. The swim club was in the Dolphin store, where they got supplies for their club. Like always, Haru unbuttoned his shirt and tried to climb into the swim tank. He got it halfway off before Nagisa and Makoto noticed and stopped him. Makoto, upon seeing new bites, faltered for a second then quickly pulled down Haru's shirt to cover his torso again.

Nagisa saw them too, and in a moment of innocence, voiced his confusion.

"Haru-chan, why do you have bite marks all over? And why did the others say "shark" when they saw them?"

Kou overheard and put her face in her hands. Makoto and Haru froze.

Haru slowly turned to face Nagisa who was once again pouting.

"I really must go now." Haru said slowly, whilst his face turned a faint pink color.

"Eh?! Wait, Haru-chan-!" Nagisa called, but it was no use. Haru walked quickly outside and began to jog home.

"R-rin." Haru murmured.

"Hn?"

"You've got to stop… biting me. The other's notice at practice. It's getting a-awkward."

Rin grinned. "Why the hell do you think I mark you in the first place? I want them to know. Now stop complaining."