The Sadness (2021)

The Sadness and Happiness are both centered around a zombie outbreak and having to survive. Both are action/thriller.
In both, the female lead is immune to the infectious zombie disease and both females make it out alive.
The Sadness is a Taiwanese movie while Happiness is a South Korean drama.

Note: isn't it funny how one is called sad and the other is called happy lol :) btw Happiness does have a good ending while the ending in The Sadness is left open ended.

TRIGGER WARNING: trigger warning for rape in The Sadness as the zombies there can't resist the urge to rape and murder (brutal and lots of gore). Happiness is a little better in the sense that it has romance even tho its slow burn.

A tragic and unsatisfactory ending.Full of thrillers.Both are heart touching. Anyone would fine similarity Between these two.

The people are infected based on their strong desire, but in this movie the virus spreads faster by sexual act.

The people in Sweet Home are infected because they're cursed but they would also attack innocent people like in this movie but they're not zombies, they can take any imaginable form of monsters.

Both are zombie apocalypse thriller/horror with disease outbreak and a life or death situation.
Both are movies.
#Alive is korean and The Sadness is Taiwanese.
Be aware of trigger warning for rape in The Sadness as the zombies there can't resist the urge to rape and murder (brutal and lots of gore). #Alive has a little bit on friendship/hint towards romance