Both are high school drama with short duration episodes.
Somewhat similar concept
one has kpop idol and other is about becoming kpop idol

Both are miniseries and about high school romance.
Both have supposedly love triangle

One is gender bender

Its similar in many ways like
- the fluffiness
-the steamy kisses
- multiple couples
-contract relationship
-happy ending for all couples.

Both are variety show where Dating is taking place between complete strangers.
The max physical contact in bed on beach was cuddling but in single's inferno was just holding hands n maybe massage

Both are about revenge and set in school as far as the latest update about the glory, also its with veteran cast.

Both have marriage first then fall in love but one is about office romance and other is university.

Similar cause both are married and then fall in love slowly.
Different cause one is about revenge and other is where the husband wants to protect her

The story is totally different but both have a kid in the plot line although in PL the kid comes in later half pf the show whereas in UL from beginning.
UL is with a calm and composed man and he rarely gets angry

Both have body swap and there is area between afterlife and earth
But one is about revenge and normal life whereas the other is supernatural and ghosts.

Similar cause Rescue services involved and different cause one is about landslide prevention and other is rescuing from oil platforms

Similar cause both are about saving a town or city from destruction and someone from main cast will end up dead
Different cause one is related to fire and other to mountain landslide

Both are esports
Both have celebrity FL
Both have good looking FL ( i thought its the same one but it isnt!)