Hey, everyone! This idea came to me a while ago, and I had the urge to write it up but never got around to uploading it. Since I'm back in the mood to write, though, I thought I'd put up this along with my previous upload for Stupid Inner Voices to tide you over while I finish the next chapter of Please Don't Cry ^^

Disclaimer: I don't own Sailor Moon or their characters.

Behind Closed Doors

By PazaakGirl

Mamoru presses his ear to the door before him… not ready for what dark secret he is about to hear.

Mamoru sighed as he felt the rush of the air conditioner's cold wind wash over him. The arcade was the perfect place for him to relax after a long day at university. The constant beeping of the game consoles and the idle chatter filled his ears, and he felt the tension in his shoulders ease away at the familiarity of the place. He'd been in there so many times it was like a second home. The sight of the arcade brought images of a coffee, a bowl of chocolate ice cream, and Usagi…

He, like always, scanned the place in habit and sighed. There was no sight of a blonde odangoed girl in the arcade at all.

"Where are you, Usako?" Mamoru whispered to himself, feeling his hand twitch at the need to touch her and hold her. "I need you… I need to kiss you right now."

He sat down at the counter on the stool nearest to the employee's lounge and the storage room, waiting for his best friend. Surprised that Motoki was not behind the counter he guessed he was out the back. So he opened his textbook and waited for the two most important people in his life to make their entrance.

A few pages into his reading however, and Mamoru noticed he could hear voices behind one of the doors. At first he paid no attention to it, and resumed his reading.

But after a while, it couldn't be ignored.

He furrowed his brow as he concentrated on the sound.

It sounded like…

…moaning?

"Mmmm…."

Mamoru's eyebrow rose as he shook his head. He figured Motoki had a girl out the back. Glancing at his watch he wondered where his own girlfriend was. Usagi had a track record for being late, but she always made an extra effort to be on time where a date with Mamoru was concerned.

"Oooh… that's so good…"

He sighed. He did not want to hear Motoki getting it on with someone in the back room. If Mamoru had enough bother, he'd bang on the door and yell at Motoki to get his ass out of the lounge and serve certain waiting customers. He needed his coffee and ice cream, almost as badly as he needed Usagi. He didn't need to hear snippits of his friend's sex life.

"Don't stop… just a little bit more…"

Still, he couldn't help but listen, and his mind began to wander.

Somehow, that female voice was a little familiar.

"You still want more?"

"Oh, YES! YES!"

The louder the voice got, the harder it was for Mamoru to shake the fact that he knew that voice.

"Motoki-kun, please!"

Mamoru froze.

That voice!

Motoki's chuckle could be heard from behind the door. "As you wish, Usagi-chan."

No… No! No, no, no! It CAN'T be!

Mamoru had to stop himself from falling off the stool, and he immediately scrambled over the counter, knocking the straw dispenser over. He pressed his ear to the employee's lounge door.

"Try this."

"But… are you sure?"

"It'll be fine."

More of Usagi's moans could be heard as she swallowed… and Mamoru's knees began to feel weak, both with desire at the sound of his girlfriend's voice, husky with pleasure, and with shock at the reason for her delight. Despite the situation, Mamoru felt himself growing hard at the thought of her doing the same to him, and he cursed himself for being turned on by it.

"Oooh… oh, wow… it tastes so good Motoki…"

He laughed. "It's better with chocolate sauce, isn't it?"

Mamoru could hear the voice – definitely, distinctly Usagi – moan in pleasure and he collapsed on to the floor.

They couldn't… not Motoki and Usagi… he'd… she'd… they'd never…

"OOH! Can I have that too?"

Motoki laughed. "I don't know... it's pretty special..."

"But... I want… I want that! Please, don't tease me, Motoki-kun! I want it so badly!"

Motoki chuckled and Mamoru closed his eyes, not wanting to know what was going on. His brain was still trying to register that Usagi and Motoki were going at it behind his back. Usagi, the love of his life, the reason he got up every morning with a smile on his face, and Motoki, his supposed best friend. A tear or two began to slip out from under his closed eyelids. He never made love with Usagi, because he respected her virtue… he wanted their first time to be special for them… and now…

More moans and giggles of delight escaped Usagi's lips and Mamoru slumped against the door, wondering what he'd done to deserve this infidelity. What Motoki would say if he knew Mamoru was listening to them. What Usagi would do if she found out he knew about this. He gave her everything she wanted. He respected her, cherished her. But… did she resent the fact that he never made a move on her? Is that why she was in the employee's lounge… with Motoki… doing… having…

He didn't want to think about it, but the sounds from the room were invading his mind.

"Promise me you won't tell Mamo-chan." He heard Usagi say, and he felt like a dagger had been plunged into his heart.

"I won't Usagi-chan. You have my word. This is just between the two of us. He'll never know."

The dagger twisted itself as it ripped through his chest.

Mamoru suddenly heard Usagi scream in joy and he put a palm to his face, covering his eyes. Images of Usagi naked, her perfect body arched in pleasure as Motoki drove into her filled his mind and he couldn't shake the feelings he had at that thought. His whole body seemed to resonate with the anger and pain. Shuffles and clatters of what sounded like plates and cutlery echoed behind the closed door and an image of Usagi lying on the coffee table in the lounge came to him next. The thought of someone else's hands and mouth exploring her body… Usagi's sigh of satisfaction wrenched out a few more tears of frustration from Mamoru's eyes.

"I think it's time for round two. Ready for more?"

"YES!"

He couldn't take it.

He heard all he needed to hear, and all he could take hearing.

He had enough.

Mamoru stood up and took a few steps back before crashing into the door of the employee's lounge, unhinging it and sending it clattering to the floor. His blood was pounding at his ears, heart racing, and he was ready to kill Motoki for stealing Usagi, and then his girlfriend for cheating on him. But when he looked up… his heart stopped altogether.

Usagi sat on the couch, eyes wide with guilt, trying to wipe the evidence from her mouth. Motoki stood frozen, like a deer caught in the headlights. His mouth dropped open in shock at seeing the university student towering over the broken door. He walked towards him tentatively. "M-M-Mamoru… look… I can explain…"

Mamoru looked at the stuttering arcade worker, then at his girlfriend, eyes darkening in rage at the liquid coming down from her mouth. He looked at the table and his fists clenched.

This was worse… so much worse than he imagined. He knew that was an irrational thought… but he couldn't help it. What he saw before him… he glared at the scene before him, his entire body shaking with suppressed anger. The emotional turmoil he felt at hearing them in the lounge drove him crazy. He could feel the repressed feelings surging through him, the feelings that built up as he listened, the rage he felt picturing them making passionate love behind his back.

How could they! How could they do this to me?

Finally, Mamoru couldn't hold it in any longer.

"I TRUSTED YOU! HOW COULD YOU BETRAY ME LIKE THIS?"

Usagi stood up, stumbling towards the raging upper-classman. "Mamo-chan… I can explain…"

"NO! YOU KNEW! YOU KNOW HOW I FELT ABOUT THIS! AND YET… yet…"

A fully dressed Usagi and Motoki winced, frozen in horror, as they watched Mamoru continue to explode. He picked up the empty container in disgust and threw it against the wall.

"MY CHOCOLATE ICE CREAM! HOW COULD YOU FINISH IT?"

Whoa, what were YOU all thinking? You PERVERTS! Hahahaha. Just kidding =P