Both dramas involve ML and FL who are enemies. In FH, FL lost her memory but in SL, ML is the one who lost his memory. SL has fantasy genre in it

In both dramas FL and ML are rivals. FL lost her memory and found by ML. In AYTO, ML lied about their relationship

Both dramas involve married couple on the verge of divorce. But slowly learn to fall in love again.

Both involve marriage of convenience, unproblematic inlaws and mature leads. Leads in both dramas work to make their marriage happy and they have many sweet moments. YAMY is more career driven plot but PBMY is more family centre plot since they have kids (suit the title)

In both dramas, the leads lost their kids which eventually lead to their marriage go astray. In IHAL, the ML is the one from the rich family while the FL is the rich one in QOT. Both FL became cold after losing their kids. Unlike ML in QOT who have the backbone to stay loyal and ask for a divorce, the ML in IHAL had an affair because he felt lonely. Since IHAL is amuch longer drama, you gonna get a very makjang style drama. It is still fun tho

Both are amazing highschool romance. They gave viewers this warm feeling and heart-fluttering moments that make us fall in love with the movies.

Both ML in the movies are kind and sweet but KNT ml is more the friendly and charming type while OSD ml is more tsundere, blunt type.

But FL in both movies are similar. Shy, timid but kind. For me personally, OSD fl is more relatable because despite the shy and timid personality, she actually has social life and actually have no problem communicating with people (unless when it comes to her feelings)

The leads took time to start their relationship in both dramas. Some people may thought it is dragging but I love watching the leads slowly build their relationship before they officially start dating

Both dramas gives depth about the leads feeling that makes us understand why they fall in love with each other. I love YAMG. If you feel unsatisfied with how fast Jing Jing accept Yu Tu after he breaks her heart like me, you definitely need to watch IMLY. I love watching ML in IMLY struggling to win his FL back. Plus both dramas dont have love triangle.

Both have fantasy element. COALG focus more on mystery and conspiracy while Island go deeper into the fantasy story. But both have subtle romance story. If you like fantasy drama with a slight romance, both dramas are definitely recommended

Both dramas will bring so much tears. So prepare tissue. LOTS of tissue.
Both have time travel story. But IBTYG involves the son time travel to the past to give his mother a better life while GBC involves a married couple went back to the time before they married

both involved arranged marriage and cheating husbands.
In MT, FL kindness eventually win over her husband.

Love old man-young lady couples in both dramas.
FY couple has almost 10 years gap while OMSHOM couple has almost 20 years gap.
Both couples are cute and they are very honest to each other.