Dramas with an unhealthy/obsessive friendship

If possible, I want shows with a friendship where one of the two or both friends are obsessed with the other. Unhealthy friendships.

It can be that one of them has a one sided relationship on the other or it could be a platonic obsession with the friend (preferably in a "positive" way and not for revenge). 

The more obsessed and unhealthy the better lmao. I don't mind spoilers too if this is treated as a "plot twist".

Thanks in advance.

 emeraldarrows:

Marry My Husband 

Watched that but thanks! Liked it.

 winmyheart:

Most of these are person A's unhealthy one-sided crushes on person B

In True Beauty Sujin (Seoho's childhood friend) grows to be possessive of him

In Light on Me Sohee has a one-sided crush on Daon but sort of almost acts as if they're already in a relationship, she's very possessive of him and rejects anyone showing interest in him behind his back

In My Lovely Liar Syaon is crushing on Doha, and she plays with his feelings and manipulates him in order to gain his attention, once she took advantage of his trauma and threatened to kill herself

In The Director Who Buys Me Dinner Denis feels like Dongbaek is the only person who truly understands him, therefore he becomes obsessive of him and extremely hostile towards Dongbaek's boyfriend Yudam

(Not sure if this counts) In Color Rush Yeonwoo begins to be obsessed and dependent on Yoohan, and has thoughts about locking him up etc, they end up together in a rather healthy way but only after a lot of ups & downs

Thanks for the recommendations!