Technically it was okay. I mean, it was superfast, like the other 3/4 stories in this series, which isn't my favourite thing, but it's not a big deal. The relationship and interactions were really wholesome. However, I'm not a big fan of the age-gap trope. Actually, I tend to avoid it because I usually just end up hating it. Especially when it includes the characters knowing each other since when one of them was underage, or literally a baby. And here that's the case. There's even some mention of Dean having horny thought about Larkin when he was still a teen which is just ew. 
But I'm not going to rate it because I knew that I won't enjoy it even before I started it, so my rating would reflect my attitude and not the story itself.