"What are you, Marco? Chicken?" Janna cackled as she swirled an unlabeled, plastic water bottle full of a thick, red liquid. To the untrained eye, the contents looked like badly stirred Kool-Aid—the kind Star makes because she adds way too much mix to the water. Yet, according to Janna, the glimmering liquid was actually hundred-percent, pure demon's blood. How she was able to get the bodily fluids of a magical creature in a water bottle, Marco did not want to know.

"Hard pass," he held up a hand as he leaned against a concrete wall.

"But it'll give you cool demon powers," she tried hard to convince him. "There's a full moon tonight and a demon moon in the Underworld. It's extremely rare for them to happen at the same time, and legend says if you drink demon's blood on a night like this, you'll get powers."

"So," Marco shrugged with indifference. He was already having a crappy night surrounded by awkward teenagers and dizzying strobe lights. After being begged over and over by Alfonzo and Ferguson to visit Earth because life was so boring without him, Marco decided to put an appearance at Echo Creek Academy's homecoming. It was going as well as one expected. High school was already a weird wasteland of hormones and homework, so returning for a day after being away on Mewni reminded Marco he wasn't missing out. The students were still largely the same, his friends were still largely the same, the football team still stunk. It was like life was set on standstill and the only things in motion were him and Star.

In more ways than one, he smiled thinking about his new girlfriend. If only she were here right now and not busy with princess stuff. They could have danced and maybe spiced up the lame party in the school's gymnasium with a bit of magic. However, he figured the real reason why she declined the invitation was that she didn't want to be around Jackie after what happened at the end-of-the-year party confession. Yeah...that was awkward.

Across the way, the chill blonde was busy chatting with a couple of the popular guys by the punch bowl. It was good to see her moving on after she and Marco broke up, so he could move in with Star. She likely knows Star and I are together, he mused.

Janna followed his gaze and shook her head, "Your loss, Diaz. I'm sure Star would love a cute, demon boyfriend."

"She's had enough of them," Marco said a bit too hastily, causing Janna to raise an eyebrow. He just wasn't in the mood to think about her ex-boyfriend, Tom Lucitor. The Prince of the Underworld was around more since he and Star were both royals, and the tension between the two wasn't fun.

Marco's former classmate shrugged before walking away, "Suit yourself."

Alone again, Marco observed the homecoming dance and sighed. He would much rather be on Mewni cuddling with Star and helping her unwind after a long day of princess duties. That was his job as both her personal squire and boyfriend. Maybe I should sneak out, Marco let his hand graze the handle of his dimensional scissors in his pocket. They seemed to be calling him. Let me at least say 'hi' to Jackie, he decided because avoiding her was kinda rude. Sure, it would be awkward, but he needed to be nice.

Taking in a deep breath for courage, Marco strode across the dancefloor, squeezing between dancing couples and chatting friends. What was he going to say to his ex-girlfriend? "Hey, how's your life been since you dumped me for being hung up on Star and abandoning you for most of the summer?" Nah. "I hope you're doing fine, how's life?" Maybe. Ugh, I haven't gotten any better at speaking to her after all of this time! Why was interacting with Jackie-Lynn Thomas still such a huge deal? When Marco asked Star out on a date, he did it with no problem. Talking to her was more natural in many ways. They were best friends who knew each other after taking the time to develop a strong bond between them. Marco and Jackie didn't even talk to each other before Star pushed them together. Man, this relationship was a bad idea.

The closer he got to Jackie, the drier his mouth became, and he needed a drink. Not wanting to draw attention to himself, he snuck to another snack table and picked up a random water bottle, chugging the entire drink down in one sitting. Hmm, he chapped his lips. This was the strangest water he had ever had. It was thick and sticky on the way down with a faint hint of...cherry? Raspberry? Some kind of berry. Maybe the eager homecoming club decided to buy flavored water.

Now refreshed, the moment of truth came, and Marco let out a deep breath. Here goes nothing. In his head, he rehearsed a few different greetings and friendly phrases to get a conversation going as he closed the gap between them. Jackie looked up from her company and made a face that was at first difficult for Marco to fully read. She seemed surprised to see him and a little sad—which was what he expected.

He cleared his voice, and said in a curt voice, "Hello, Jackie."

She replied in kind, "Hi, Marco." Silence fell between them. Great job, Diaz, he could just kick himself. Say something to her.

Marco was about to speak when a shaft of silvery moonlight fell on his shoulders from the windows. For some reason, it made his body feel really hot. Unbearably so. Maybe it was the suit jacket. He shrugged it off but found that his back itched like crazy. Oh no, he groaned. He was likely having a reaction to his back sweat. Then the itching didn't go away, in fact, it became painful, causing him to writhe on the ground in agony.

As he hollered and cried, the music stopped, and all of the teens and chaperones gawked, screaming in horror. Why aren't they helping me? Marco clutched his head which felt like hammers were pounding nails into his skull. Why were they pointing and yelling at him? By the time Marco came to again, he rose to his feet, his body feeling heavy like lead.

"Wha...?" He stared at the long, fingernail-like claws on his hands. Black wings pulled on the muscles in his shoulder and a long, slender red tail twitched alongside his leg. No...nononono! That wasn't cherry flavored water...Marco stumbled into a table, spilling punch and snacks all over the ground. The bowl caught on his horns and spun around spraying droplets everywhere. I gotta get outta here!

He sliced open a portal to Mewni, hearing Janna as he left, "You'll thank me later, Diaz!"

Back in his room, Marco was a whimpering, shivering mess. His shirt had been torn to ribbons and he was scared. What did the demon's blood do to him? Was it permanent? In his panicked haze, Marco remembered Janna talking about a demon moon and he turned to see the red celestial body glare at him—mocking him. Welcome, demon boy, it seemed to glower.

He slit a couple of holes in the back of his hoodie to make room for his wings and zipped it up. It hid most of his body, and it gave him the allusion of normalcy. But what will Star think? Unfortunately for him, he could hear her cheerful humming as she approached his room.

"Star!" His fangs made him lisp her name, "Don't come in here!"

But, the cheery blonde didn't hear him and burst through the door, "Heya Marco! Wait a minute—"

In the darkness, Marco could see her blue eyes glow, lit up by her charging wand. "What are you doing here, Tom?" She barked, taking a big step forward. As her eyes adjusted more and more to the half-light, the angrier she became. "You're not, Tom..."

Before Marco could reply, a Narwhal Blast knocked him over, pinning him to the ground. When he shoved the heavy, magical whale off of his body, he was met by a green glowing wand just mere inches from his face. Wow...seeing the fierceness in her eyes and the determination to kick his butt took his breath away. However, he forced himself to focus on calming her down—he watched her kill Toffee before his eyes.

"Star," he put on his "woobie" eyes, "It's just me."

"How do you know my name?" She raised an eyebrow.

"It's me, Marco," he got up and hugged her.

"Marco? What happened to your cute body...?"

He froze and pulled away, feeling ashamed of his appearance. What if Star stopped liking him because of his demon body? Although he didn't see his reflection—he never wanted to—Marco knew he had to look like an ugly gargoyle with fangs, wings, horns, and a tail.

Star pulled him in close, so she could hold him and cup his cheek, "You look even cuter."

"What?!" Marco stammered, blushing.

"Oh, Marco. You're such a cute idiot no matter what you look like." Star smiled and reached up to lock lips with him. He held her closer, melting in her sweet embrace as he deepened the kiss. The combined glow of their cheekmarks lit up the room in a soft glow. "Mmm, Marco?" Star paused for a second.

"Yes, Star?" He shot her a silly grin.

"Can you watch the fangs?"

"Sorry..."