This for the first prompt, I couldn't help tacking on something for myself at the end. I hope this is what you wanted so tell me if you liked it (or what you didn't like)
A TRADITIONAL THANKSGIVING
Happily humming to herself M'gann grabbed a wooden spoon and began stirring the contents of a bowl cradled in her arms while walking the length of the countertop inspecting all of the things she'd laid out and comparing some of them to the cookbook floating beside her. Coming to the end where a turkey sat in a roasting pan ready to be prepared she gave herself a nod and smiled. The team was going to love the meal she had planned for them.
"Wow what's all this? It looks like you've got enough here to feed an army" said Zatanna as she and Artemis wandered in the kitchen together.
Putting the bowl down M'gann went over to hugged them both, she was so glad that everyone on the team had agreed to come over today even though she hadn't told them exactly what it was for. Artemis and Zatanna were the first to arrive and since they were here it didn't seem like there was any need to keep it a secret anymore.
"I'm making Thanksgiving dinner!" she said with a big smile, "I've got mashed potatoes, cranberry sauce, sweet potato casserole, sweet potato casserole and of course the turkey."
Both of the girl's expressions changed to one of puzzlement when M'gann listed the last item but it was Artemis who voiced her confusion first. "I don't want to be a downer but why a turkey?"
"Because that's what everyone eats on Thanksgiving, a roast turkey. Right?" said M'gann as her tone made a rapid transition from confident to questioning and finally to mildly distressed. "They showed it very clearly in the TV special, I watched it five times."
"Um, M'gann. Just how old was that TV show?" asked Artemis pointedly.
Not wanting to drag this out Zatanna jumped in to explain. "What Artemis is trying to say is that turkey has been out of style for, ah, several decades. Nowadays it's traditional to celebrate Thanksgiving with roast girl meat."
"Oh" said M'gann dejectedly, "I… I didn't know that." She'd put so much effort into making a holiday meal she hoped her friends would enjoy and somehow she'd messed up the most important part.
Of course she knew they wouldn't blame her, on Mars they didn't eat girls at all. But at the same time she didn't feel like she should be able to hide behind ignorance - she passed the shops selling girl meat everyday in Happy Harbor and she'd even tasted it during Spirit Week when the school picked a cheerleader and they all watched her being skewered alive and then slowly cooked over an open fire. Her friend Wendy had tasted pretty good.
Seeing how crestfallen she looked Zatanna wrapped a comforting arm around her shoulder, "It's not a disaster M'gann. You still made all this great food for us. Why don't we just forget the turkey and call it a nice team meal."
M'gann sighed as the other girl gently embraced her from the side. "But I really wanted to show everyone the perfect Thanksgiving, I was even preparing this great five herb seasoning for the roast" she said gesturing at the bowl on the counter.
"Well what's stopping you from using it?" asked Artemis, "I mean if we gave you some help couldn't you roast yourself?"
"That's a great idea!" Zatanna exclaimed, "I bet nobody's had the privilege of trying Martian-girl meat before, it could be the best Thanksgiving ever. What do you think M'gann?"
M'gann was justifiably surprised, "You'd really want to eat me?" Their enthusiastic nods left no room for interpretation but she knew that the real issue lay in the fact that being eaten would at some point involve her quite definitively dying. But at the same time her two friends looked so hopeful and excited at the idea. And she'd already invited everyone else on the team; she would feel really bad if she let them down. "Alright, how do we start?"
-A SHORT TIME LATER-
The girl sized roasting pan was just over six feet long, too big for many kitchen counters and so it came with its own cart that allowed it to be wheeled up to and then rolled into the kind of oven they needed.
Standing beside it M'gann nervously removed her crop top sweater and handed it to Zatanna and then started unbuttoning her shirt. As she handed over each article of clothing the idea that she was going to die became more and more real. Slipping off her pink cotton panties she realized there was nothing left to take off which meant that it was time to get on the roasting pan.
Studying M'gann's clothing as she folded it up neatly Zatanna absently asked "Hey, do you think this outfit would look cute on me too? Do you think I should take it?"
For a second the question seemed odd before she tapped the side of her head for being so short sighted. "Hello Megan! Of course you should take it; I won't be wearing it ever again."
Once she was on the pan Artemis helped position her hands over her stomach and tied her wrists together with twine while Zatanna was doing the same with her ankles. With small brushes they set about coating her body with the final recipe that she'd been working on earlier. It wasn't cold like she thought it would be and she could smell the small bits of herbs and spices as it settled on her skin.
As Artemis got to her breasts M'gann drew in a sharp breath. The sensation as the soft bristles danced across her nipples was certainly not something she had been expecting to feel while being prepared for cooking. Artemis smirked and repeated the action, clearly aware of what effect it had on her.
"Already enjoying being a meat girl?" she said with a smile as she paid extra attention to the way she coated M'gann's bust, caressing her tits until M'gann finally gave in to the pleasure and groaned appreciatively. "Hey Z, are you just about ready to give M'gann some extra flavor down there?"
M'gann didn't know what she meant but Zatanna did. The other girl began to slide her brush along M'gann's pussy far more than was necessary to prepare it for cooking, teasing around M'gann clit until the Martian girl was moaning obscenely and all but begging to be touched there.
Captivated by the scene Artemis bit her lip and watched her soon to be dead friend withered in pleasure as Zatanna finally granted her wish and tweaked the little numb letting M'gann cry out in ecstasy. Flipping the brush over and working with the awkward placement of her legs Zatanna got the handle to M'gann's entrance and pressed it confidently into her moist tunnel.
M'gann was breathing fast now and not caring about the lewd sounds she was making as Zatanna fucked her with the improvised dildo, her thoughts about dying and being eaten mixing freely with the pleasure she was experiencing. Would Conner get this kind of enjoyment when he was devouring her flesh she thought? Would she have offered herself up as meat sooner if she'd known it would be this good?
Feeling herself reach a crescendo M'gann shuddered and squirted clear fluid all over Zatanna's hand. Raising it to her mouth the female magician stuck out her tongue and licked at the girl juice, messily lapping it up and getting it all over her face. "Mmm that's good stuff" she murmured and offered her hand to Artemis who sensually sucked each finger clean.
Wanting a little more Artemis pulled Zatanna closer and kissed her with an open mouth, both girls sucking each others faces trying to get every last drop. Parting lips Artemis looked hungrily at Zatanna for a moment but then remembered they were still in the middle of something. "It is good; she's going to taste perfect once we roast her" she agreed.
M'gann idly wondered who would be eating her pussy after it had gotten so much attention. She could probably ask but she wasn't sure if it was bad etiquette, since the one thing she did know was that once she was meat she didn't have any say in what happened to her. Making it seem like she was dictating who ate each part of her might be rude and she didn't want to ruin the holiday.
Her thoughts were interrupted when Artemis snapped her head to the side and shouted "Wally!" and "Get out of here you pervert."
Looking over the edge of the tray M'gann could see that Wally had snuck into the kitchen and was coming over to join them. Her smile became one of awkward embarrassment since there was nothing she could do to prevent him from seeing her naked and her cheeks went even redder when she realized he'd probably seen her performance a few moments ago. However it shouldn't bother her if he did she thought, in a few hours he would probably be chowing down on one of her breasts anyway.
Zatanna seemed to have similar thoughts as she pushed aside Artemis's objection. "He's going to see it later so why not let him look while she's still alive, I mean she's already on the tray so she's meat anyway. Come over and enjoy the view Wally" she said and waved her hand over M'gann's shiny naked skin.
M'gann was intently aware as Wally approached and made a leering examination of her body. She'd brushed off his many lustful advances but now that she was officially meat he'd be within his rights to do whatever he wanted to her.
"Oh yeah, she looks like she'll be real tasty. But then you always looked tasty to me babe" he said still flirting shamelessly. Looking back up at the others he added "You know I'd be happy to give you two an extra hand to finish preparing her, maybe give the cooking a man's touch."
In response Artemis threw out an arm to block him and firmly stared him down. "You'll be keeping that baster of yours in your pants if you know what's good for you. We're all going to be eating M'gann and some of us don't want to taste your special sauce inside of her."
Having gotten over her embarrassment M'gann giggled at their antics. She was really going to miss the way those two argued with each other. "Thanks for offering to help Wally but I guess Artemis is right. I hope you enjoy me once I'm done cooking."
Wally followed his cue to get lost but at the last moment Zatanna's had a devilish idea. "Hey, how would you like to be in charge of cooking Artemis for Christmas?" she called out as he disappeared around the corner.
"Shut up" the blonde hissed and M'gann could see her face turning beat red. Obviously the suggestion of giving Wally free reign over her body had given Artemis a lot of embarrassing thoughts to consider.
With the kitchen back to being the girl's domain they added garnish and vegetables around her and finally it was time to go in the oven. Zatanna opened the big door and Artemis rolled the tray up and unfastened it from the cart. "Well it was nice knowing you" she said as she gave the tray a push so that it slid in smoothly on the well oiled rollers.
"It was nice knowing both of you too" M'gann called back as her head entered the warm oven followed by the rest of her body. She could hear the door close and the outside latch lock into place cutting her off from her last human contact. The heat was already starting to feel oppressive and without the outside light the small coffin like space seemed even more claustrophobic.
M'gann tampered down on the dread that filled her by reminding herself that she'd be dead soon anyway. It was certainly an interesting way to go, humans had such fascinating customs and they'd made the whole six months she'd spent on Earth feel incredibly special.
-OPTIONAL EXTENDED ENDING-
"So…" Zatanna started awkwardly, "How is everyone liking it?"
"It is certainly… unique" answered Kaldur stiffly.
"It's kind of, err, gamey" added Dick.
Seeing the others agree Wally's shoulders slumped, "Yeah, let's just admit that it looked a lot better than it tastes."
Silently a plate was passed around and everyone transferred their remaining portions of M'gann onto it. When it reached the end of the table Conner bent down and placed it on the floor where Wolf sniffed the alien meat inquisitively and then began gobbling it up.
Seeing how dour he and the rest of them looked Zatanna leaned forward and got Wally's attention. "Hey, it's not like today was a complete loss" she reminded him.
The speedster's face lit up as he remembered what they'd worked out while M'gann was busy cooking in the oven. "That's right! We've still got a whole month to prepare Christmas dinner" he exclaimed excitedly.
Sitting between them in the nude Artemis let out a mortified groan as she felt Zatanna lean into her and boldly reach between her legs while Wally happily snuggled against her other side and squeezed one of her breasts. The rest of the team chuckled in good spirits as they glanced at the shiny new meat tag attached to her ear bearing the initials W.W. and Z.Z.