I wanted to like this, I generally love a monster romance but nothing happened and I kept cringing (partly because I listened to it as an audiobook which doesn't help). 

Celeste just didn't give me much, and all I remember is her being prejudiced about most of the monsters and being worried they would kill her if she went out alone. Theo was patient and kind but again, not a lot stuck out to me about him either. 

Wholesome I suppose and definitely low angst but not for me.