"And that's a Dragonfly promise!" (Comet dragonfly x sister! Reader)

A new home!

You sit in a comfy chair as your brother parents stand in front of you, talking with the supposed "principle" of this school. Comet, who WAS beside you was now inspecting the office "so you say your from another...dimension?" The principle says though you mentally note that he talks like he has a stuffy nose, just as you thought that the lights in the room had suddenly gone out, then on...then out. You, moon and river all looked back to see comet flicking the light switch on and off, an awed look on his face before he turns to face the three of you "and you said there was no magic on earth" you gasp and hop out of your chair "how'd you do that!?" You say as you stop beside him and eye the little switch amazed "like this!" He says and flips the switch a few more times. Moon can only watch in silent disappointment before she turns back to the principle who continues.

"Yeah...uh this isn't gonna work" the principle says unimpressed but just as he does your father lifts the chest of gold and treasure he set down earlier and opens it, once he does the principle nearly hopes out of his chair "they're gonna love it here!!" He says ecstatic. The light switches on and off a few times more before moon sighs "they're...going to need a guide" your father says watching as comet encourages YOU to flip the switch off and on again this time.

You walk out of the office side by side with comet while your parents walk off the school grounds and enter the carriage, manfred cuts open a portal as your mother waves to you both from the glass less window, you both wave back and shout your goodbyes. Once they've left and the portal closes you hear the principle calls out on a speaker to someone named "Marco diaz" you look to comet only to find that he's found something else to investigate "hey y/n look!" He says as you walk over to him "what is this?" You say as you poke the odd sink looking thing. Comet leans down and pushes down a small round button, then suddenly water spurts out and surprises you both.

As you and comet get prepared to fight the water spurting monster you hear

"Marco! I want you to meet our new foreign exchange students, comet and y/n dragonfly!"

"HUH?"

The principle smiles and Marco looks over to you and comet, comet has decided the best way to defeat this beast was to chomp it to death while you decided to take off your shoe and beat it to death...though both your tactics weren't very effective.
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The three of you were walking down the hallway as Marco explained why he was the 'misunderstood bad boy' but while he did you and comet both explored the school and said hi to all the people that walked by.

By the time Marco was halfway done with his speech rant he moved you away from glass, stopped comet from tripping on a loose tile and closed a locker before comet could walk into it, but even through all that comet wasn't paying attention at all well that was until now "frankly I like taking risks! And would welcome a little danger in my life!" Just as Marco finished that thought comet grinned at you and turned a stray butterfly into a huge gut eating monster, the monster immediately turned to Marco and screeched in his face before turning, picking up a kid and flying off.

Marco Quickly hides behind you absolutely terrified "wha..what the heck was that?!"
Comet smiled sheepishly at Marco noticing his reaction "Oops..heh.." you look behind you and smile at Marco unfazed, this sort of stuff happens on mewni all the time. "I thought you wanted a little, danger!" Comet says before Marcos backs away from the both of you eyeing you both suspiciously "who..are you?.." comet smiles while he takes your hand "well I'm a magical prince from another dimension! And this is my sister!" You smiled at Marco since he looked so weirded out "I'm y/n dragon fly and this is my brother comet dragonfly!" You said since comet wasn't very informing on your actual names. Comet then used his wand and created a rainbow above the both of you...which then caught fire, you looked to Marco as he stared back unblinking "welp! That brings us to the end of our tour, I'm going home now" he said as he turned and walked away with the most unfazed smile on his face. Once he did comet raised his hand and waved him out "bye new friend! See you tomorrow!! Bye!!" You laughed as you started to see Marco running away as your brother kept on with the farewells.
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