Hell Phone, Book One

Have I mentioned how much I hate cliffhangers? 
Everything else about this first book (no idea when that second is coming, grrrr😤) I quite enjoyed. 

The story: My preferred level of creepy - not too gory, not too sad, bit silly, more about the mystery than the spooky. 

The characters: Obviously angled towards a younger crowd than me, but good friends with minimal friction that accept each other's foibles and support each other regardless is a timelessly appreciable trope.

The illustration style:
Hurray for full vibrant colour !
Something about the character illustration reminds me of Betty Boop.
There's probably a whole subgenre that caters to the idea, but in multiple-source-recommendations meander through graphic novels, I don't often come across one frequently playing with the clothing fashions of the characters when it's not central to the plot. It was fun, and added more variety to the page.