From what I've seen most of the K dramas on Netflix have 8 to 16 episodes and tell a complete story which makes them the perfect length if you don't want to commit to a show spanning hundreds of episodes. Some of my favorites in addition to Beyond Evil and Extracurricular which were both top notch:

My Name

Itaewon Class

Kingdom

The Glory

Stranger

Sweet Home

Law School

Hotel del Luna

Bloodhounds (currently watching)

These are all over the map thematically so hope you find one or more you enjoy!