What I didn't expect to see is Eunmi fainting at the sight of the genie's sudden appearance. Because it wasn't mentioned at the end of the previous chapter, it didn't seem that way. It's sweet of Eunmi's grandma to leave a thoughtful gift in her possession. Other than to bring her happiness, she might've also considered that Eunmi would need a companion at this time so that she won't be lonely. There's something comforting about Myungsoo's presence. He is attentive to be able to notice even the little things. Based on how she reacted to his statement, it can be determined whether she is being honest. He seems taken with her already. Cuteness is the factor that makes one soften up easily.

Ch. 2 typos:

She was clearly interesting in what L had to say.
Correction: interested

She stretched her out, inferring L to shake it.
Correction: She stretched out her hand and inferred L to shake it.

He chuckles at the cute girl a few centimeters away from him as she lowers her head offend.
Correction: looking offended

This is a good start of the story. The package that Eunmi received is an unexpected surprise and a mystery. It makes me wonder if this could possibly be connected to her late parents' will. Whoever sent this item to her is unknown. It's expected of Eunmi to react this way since she doesn't believe in the supernatural or fairytales. This means that Eunmi is a realist. It seems that Myungsoo has a playfulness to his character because of the impression that he gives off at his entrance into the story. Leaving the readers hanging for more is a good tactic to keep them interested.

So far, this is the second fic that I've seen featuring Myungsoo as a genie. Though, the plot that you're working on for this story is different from that of "Wishes" by dearlybeloved. The characterization of Myungsoo in this fic seems to be different from his character's portrayal in "Wishes." So, this won't look too similar that the differences can't be determined between yours and her fic. It'd be interesting to see what kind of twists you'll be putting into the story.