Hi Hi, Myl here from Hacheeachkee
I read your comic and it's rather catchy. Honestly I thought at the beginning it was going to end up a generic, boy has crush on girl in highschool scenario, but the twist in story of the cellphone contract and the popular girl he had a crush on coming down with a terminal illness hooked me in. There are some pages where I just thought there was far too much dialogue in ratio to pictures and I ended up glazing over all the little conversations that I felt didn't really matter until something dramatic happened.
I'm always weary and cautious when it comes to a blatant narrator, this character that just hangs around nonchalantly handing the story to the reader (as I'm not a big fan of this method), unless this narrator has a significant role not yet reviled. I'm also not a huge fan of characters taking up pages to "teach" a main character or the reader about all the rules and such, like in videogames you kind of just want to get past the tutorials as soon as possible. Though finding a solution/balance to this is difficult and I understand the need to explain to the reader and protagonist what's going on, but at some points, I already was able to assume what was going:
example:
with the drop of blood on the phone and some demons popping up behind the protagonist. The simple dialogue of "He doesn't know does he" kind of already self explained that the protagonist signed some kind of blood contract.
I feel, as the author of the story your emphasis is on the dialogue, making it flow and adding it where needed. People read comics more for the artistic aspect rather than like a book for it's words, so adding too many words on one page dulls the mood. The challenge to you as an comic author is to provide as much description in as little dialogue as possible, giving the art speak for the situation instead of just dialogue and learning how to coexist with it. I do not know how closely you work with your artist, who makes thumbnails and if you know how the page is set up with dialogue included, but i see this comic having much potential.
Try to stay away from the overcliche, keep those twists and turns coming, turning assumptions like i had at the beginning of the comic into a hook to keep me reading.
Goodluck Reon!