Edge of Innocence (2017)

Both are dark and twisted tales where the males leads are obsessed. The ML's are also younger than the FL.

Honestly when i watched edge of innocence i couldn't help but think about perfect proposal, because both give that really suspenseful, mysterious vibe. Plus, both the leads in both the movies have a very ambiguous relationship and both plots take very unexpected turns. Not your ordinary romances for sure, so if you like that i totally recommend giving it a try !