More like a 3.5 for myself but because the last half of the book I really got into I raised it to a 4 star rating. 
 Cath our main character is leaving home for the first time to go to college. The author did a really great job of portraying Cath and her growth and development throughout her freshman year. Cath starts off as this young and naive child afraid to leave her room. I found her really annoying at times for that quality though. BUT! She does suffer from severe social anxiety so I can't judge her for that entirely. Just as a main character it made it really hard for myself to connect on a more personal level. She lives in her own Simon and Baz bubble writing fan fiction which I found VERY similar to the Harry Potter fandom world. Which surprises me she's writing Carry on because the whole thing read like a Harry Potter spin off world.... 
 I would've really liked if there were alternating chapters between Cath and Wren to show how each girl is coping with stresses in their own way. Cath by shutting out the world and Wren by shutting herself down with alcohol abuse. 
 When I read the last page I was like, "that was it..?" I felt like there was so much missing. The ending felt really rushed just like the character Cath did with wanting to finish her fan fiction to beat the other author. I mean what really happened that night with her sister? Does she ever stop acting like she's still a child with Levi? What about her professor? 
 This book also had a very strong family focus which I'm starting to think Rainbow Rowell includes in all her novels. There was a great family dynamic where they were all flawed in their own ways and learned to accept each other (kinda). 
 Cute and quirky but felt like it had no real conclusion.