I'm looking for a Jdrama in the mystery, crime solving, thriller, psychological etc genre but with a little bit of romance? 

It doesn't have to be a big part of (honestly even hinted is okay) but basically I want to see main leads with good chemistry, and cute interactions even if the drama is heavy? To lighten it up you know? I'm okay if it's just side characters you know?

I would prefer if they ended up together in the drama, or are a couple from the beginning to the end already, but if there is something like what I'm looking for I am okay with small but heartwarming interactions. 

Example:

(Possible minor spoilers for the dramas Liar Game and Hard Nut! but not really)

Something along the lines of Hard Nut! or Liar Game where it's not just that the main leads have good chemistry/hinted they like each other, but where the main leads actually end up together!

Liat game and hard nut are of my fav dramas, i koved them toooo much, i saw that you only watched the first season of liar game, i think you should watch second season and movie final stage, they are all very connected and awesome
thank you all so much for these recs i'm putting them all on my to watch list, i have heard of some of them but was a bit reluctant? so i guess i'll start them now.
also @abigaile i'm so glad someone enjoyed those as much as me! I started liar game 2 but I had to stop because i was really busy with uni at that time :,
Maou
N no tame ni
Ryusei no kizuna
The quiz show 2
Subete ga F ni naru
Siren