I'm sorry.. (Sans x Frisk)

First of all, this is an ESPECIALLY Frans book.
I will maybe add some side ships.
If you don't like Frans, don't read this book. There will also be a lemon as the story progresses, but it's not dire to the story, so all the cinnamon rolls out there can just skip it.
NOW BEFORE YOU SAY ANYTHING;
In this book, Frisk is 17, and Sans is 19.
Now I know, he's legally an adult but she isn't, honestly, I don't give a fuck. I have a thing for guys being older.
(ALSO I AM FROM EUROPE, SO PLEASE, EXCUSE MY GRAMMAR)
Anyways;
Frisk is going through quite some trouble. With all the nightmares, depression, fear, and unexplainable feelings for her long time friend Sans, Frisk has a lot of trouble keeping it together. Will she admit her fellings to Sans? Will she admit them to herself at the first place? Will something else get her before she can confess? And what about Sans? Does he share the same feelings? Or, better said, does he accept them?
(I DON'T OWN THE COWER, I JUST FOUND IT ON TYE INTERNET WHEN I SEARCHED SAD SANS X FRISK ART OK? OK. FULL CREDIT GOES TO THE ARTIST)