This drama has a completely different plotline from I DON'T LOVE YOU YET. But, it gives the same vibes as the latter... Probably because the director is the same.
If you are interested in the same slow paced buildup dramas, you might find it great.
Though, Kimi wa petto does have some quirky/ even mature elements but the character development goes on well and you feel satisfied completing it.
I am not recommending the old Kimi wa Petto drama because it is not related to this drama... But if you like Kimi wa Petto (2017) , do try out the old version as well...

If you are into the trope of a live in relationship with the female lead being dominated in power, this one is for you! Though both the leads are lonely in some way and need each other to complete their lives.