Based on real events X_X
"Hey did you know Moony's going out with Marlene McKinnon?" James asked Sirius casually.
Sirius raised an eyebrow, blowing smoke through his long fringe.
"Marlene? Really? How did that happen?"
"Well I'm not one to gossip but…" James impersonated Marlene with this, and leant forward in fake eagerness.
"Marlene said that Moony basically guilted her into saying yes, complaining about how he'd always be alone and nobody ever said yes to him, some shit like that."
Sirius raised his other eyebrow.
"But that's just Moony. He doesn't exactly complain, he just thinks out loud. He's not exactly filled with self-loathing either - he just sees shit as black and white."
"Well you know how dear Marly is. She's banned us from being immature about it. Says if we crack one joke she's going to dump him."
"Oh my dearest Lord. It's like she wants to torture me. She knows banning me from doing something immediately makes me want, no need to do these things. I bet she did this purely to piss me off."
"Yes Padfoot. Marlene said yes to Moony purely so she could ban you from cracking jokes, just to annoy you. All part of her master plan."
"Exactly!" Sirius blew out a frustrated puff of smoke, and offered the last drag of his cigarette to James.
"My mum'd kill me." James muttered, taking the dimp from Sirius and exhaling smoke quickly.
"I feel like a dragon." James snorted, letting the smoke dribble from his nose and giggling.
"Christ, you're a four year old."
"Oh yeah, because you'd know exactly how a four-year old reacts to breathing in a cigarette. You probably offered Regulus one on his fourth birthday."
"Oh yeah James. Because I was smoking at seven. As most seven year olds do."
"Nah, not most. It's just you, mate."
Sirius snorted, yanking James up, and they headed back into the castle.
"So how comes Remus didn't tell me about this himself?"
"Well, you and him aren't exactly speaking right now. You've been avoiding him apparently."
"Yeah. I can't spend long periods of time with people-"
"BORED." James interrupted, speeding up his pace.
"You're an arsehole mate, did you know that?"
"Like you'd ever let me forget it." James snorted, looping an arm around Sirius' neck.
The next day, Sirius and James were walking to first class together.
"So apparently Marlene dumped Moony." James said conversationally.
"Christ. What was her Unforgivable reason this time?"
"Apparently she only liked him as a friend, and the only reason she said yes was because she didn't want to be tight on him."
Sirius snorted.
"In what universe is saying yes and dumping someone the very next day a less tight solution than just saying no?"
"No idea mate. She's probably just doing it for attention. Squeezing as much sympathy as she can from the situation, aw shucks to Moony's feelings about the situation. Cold-hearted bitch."
"I really dislike that girl. She keeps coming up to me and hugging me. I swear to God, last night I stretched and she started giggling like you with a cigarette. When I asked her what the fuck she was laughing about she said "Er, not to be crude Siri, but I can see your underwear." And Peter was like, "why the fuck were you looking at his dick anyway?" Apparently she was on 'eye-level' with my balls. Fucking slag."
James snorted with laughter.
"Oh Christ. Sounds like someone has a crush on you again."
Sirius pulled a disgusted face.
"Ewwwwww. I fucking hope not. She'd probably get one of her mates to throw themselves at me until I had to shag her, like that Jenny girl, and then milk it harder than Filch when he's having a wank over Minnie."
"Eurghhh. And now that mental image is burned into my head forever. Excuse me whilst I go and hang myself from the Whomping Willow."
Sirius laughed.
"Aren't all of the Muggle Studies classes going on a trip around a Muggle society tomorrow afternoon though?"
"Yeah?"
"Isn't she in your class?"
"Fuuuuck!"
"Well, it's your own fault Siri. Choosing Muggle Studies for the sole purpose of pissing off your parents was bound to come back and bite you in the arse."
"I still maintain that it was worth every shriek."
James patted Sirius on the head condescendingly.
"Okay Sirius. Okay."
"Now I don't want anybody messing about on this trip. You are representing Hogwarts as a school, so you all better behave yourselves. Yes, Sirius?"
Sirius lowered his hand.
"But Miss, if none of the Muggles know about magic, then we're not exactly representing the school, are we?"
The Muggle Studies teacher sighed, ignoring Sirius and beckoning the class to continue.
Marlene slinked up next to Sirius.
"That was soo funny, Siri." she smirked, moving as close as possible to him and putting on a high-pitched voice.
"I wasn't trying to be funny. It's true."
Marlene let out a high-pitched giggle, linking her hand through Sirius'.
"What are you doing?"
"Holding your hand." she giggled, blinking up at him.
"Sorry, but I'm abstinent. No sex or intimate contact before marriage."
Sirius increased his pace, until she was running to keep up with him.
"But- you- slept- with my- friend- Jenny!" she gasped.
"No I didn't. She lied." Sirius denied.
"But- you- were- the one- that- told- me!"
"No I didn't."
"You- did! Last- Wednesday!"
"It must've been your imagination."
"But- you don't- have- a ring!"
"I left it in the dormitories."
Sirius immersed himself in the crowd, elegantly loping to the front and losing Marlene, thankfully. He found himself in front of one of the hotter guys in the class, Alex.
Alex had longish, light-brown hair swept into a fringe across half of his head, and dark, thick eyebrows. His friend made a comment to him and Alex laughed, bring out the two dimples either side of his cheeks.
"Sup Alex." Sirius greeted him.
Alex turned, a half-smile bringing out his dimples.
"Hey Sirius."
"So, you wanna get off with me?"
"Sirius Black. Alexander Hurley!"
Sirius and Alex broke apart, Alex blushing embarrassedly and Sirius openly laughing.
"Hey Miss." he greeted her cheerfully.
"No..public displays of affection whilst we're on a school trip!"
"Oh come on Miss, give me a break. I mean, look at him. Just look at him. If you swung this way, you'd be snogging him behind a bin as well."
Alex blushed furiously, but a little smile lit up his face as he watched Sirius admiringly through his fringe.
"Sirius Black! Oh, I don't even know what to do with you anymore! Get back in the line, both of you. Now!"
"Alright Miss. Chill. Stressing like that's not good for the ol' ticker." Sirius let his voice twang at the end of his sentence.
She ignored him, ushering them back into the line.
Alex joined his friend Liam, smile still in place. Sirius went to follow him, but before he could take a step, Marlene grabbed hold of his waist.
"Shit!" he gasped, leaping about a foot into the air.
"Why were you making out with Hurley behind the bins?" she demanded.
"Felt like it." he shrugged. He began to walk off towards Alex again, taking long strides.
"Sirius, come back here! Sirius, I me- Sirius..Ahhhh!"
Sirius heard a huge splash, and whipped around in shock.
Marlene McKinnon had fallen into the lake.
Sirius began to shriek with laughter.
Two hours later, they arrived back at Hogwarts. Marlene was being led by a tearful looking Muggle Studies teacher, bearing a startling resemblance to a drowned, very disgruntled rat. Sirius was still laughing.
He ran up to the common room, bursting through the portrait hole. His friends were still up, doing their homework.
"Guys. Guys, Oh my christ, guys. Guess what happened."
Sirius collapsed on the couch, clutching his aching stomach as he continued to laugh.
"What? What?!"
"McKinnon fell in the lake! She- she slipped on some wet moss and fell in the lake! Her head went right under, all that muddy water! She's still wet!"
Sirius wiped tears from his eyes as his friends began to howl with laughter, Remus especially.
"Oh, I am so glad I picked Muggle Studies!"