Summer Days is side story to the infamous anime/VN School Days. To be honest, I only read this novel because I was searching the keyword "summer" on a book database, and found it by accident. Summer Days is a spin-off of School Days, centered on Setsuna, Sekai's best friend if you remembered from the anime.
Guess what? I still don't get one bit how Makoto is somehow so popular that he could get as many cunts as he want.
Good novels are grounded on good characters and story, and Summer Days had none of those to begin with, not mentioning that most of the events in this
novel does not happen in the anime series (perhaps it does with the game). The set up is poor, and we never got to know why Setsuna liked Makoto in the first place, just that she somehow does.
While the narrative is readable, the story that it tells is confusing, without a shred of charm in it. The emotions are far from genuine, and Makoto is just a dick more than ever. It was actually funny when the novel try to depict him as "gentle and kind" while his actions were obvious. The motivations just aren't there...
I give this a 2/10, because the drama is somehow funny, despite being artificial, and that I didn't have access to the illustrations, which might pull up the score by one point.