Not that these two shows are super similar but they take place in the same universe.

Although Light On Me first shows up in season 3 of Best Mistake, you need to have seen all the 2 prior seasons, of Best Mistake, to understand most season 3. Because of that, I recommend you start with Best Mistake season 1.

Also both
Takes place in a school
Are about young people finding their identities/themselves

Both have:
- Supernatural creatures living amongst humans
- Both have a supernatural and human romance
- Both deal with the question "What makes someone human"
- Both are also short drama you can finish in about 1 hour