Both have leads who have father-son misunderstanding. Both have the other leads trying to bridge their gap

Both have leads that have traumatic past that relates to family. Both have leads that help overcome that traumatic past

Both started in a one night stand. Though oin Unforgotten Night, only 1 wants to continue with it while in Wandee Goodday, it was a mutual decision.

The "second" story in Love In the Air have a traumatic past and is the reason why he doesn't want to fall in love, same with My Tooth Your Love. Though My Tooth Your Love is more on the light story, Love in the Air is more on the adult/matured side

Both younger brothers are ML. Both elder brothers fell for the FL. The difference is how they handled the situation.

Prequel of how Tale of the Nine-Tailed 1938. Somehow shows Ki i Yoo Ri and Gu Shin Joo started. Shows Lee Rang's "hidden" side. A good watch if you're missing Tale of the Nine-Tailed

They are similar as both FL are skilled lawyers who wins every case and both FL is also the victim that you'll feel for and root for

They are similar as the antagonists is really evil with no remorse whatsoever. Aside from both are legal dramas, they also met justice in the end