I must say, Reply1988 is unbeatable for sure.

But if you want similar type of dramas then Dear Mayang street is the closest one, for-

*for its having similar neighbourhood type of backbone of the drama
*similarity about high school and students/teens and their silly but important for them, topics
*love triangle
*awesome FL

If you are a Lai Kuan-lin fan, then you do not need to know about the similarities between these two dramas, presence of him as ML is enough.
But talking about the similarities,
* both the dramas are high school and then college plus career later oriented.
* in both the dramas ML is caring towards the FL, however clumsy or however the FL goes bossing around him.

I agree Misty is not as dark and as toxic as drama Somebody, but certainly there is elements of similarities between the two dramas.
Take for that matter -
* The Obsessive nature of one of the lead,
*And yes of course the Mature theme these two dramas having.