My Man (2014)

Kagami Tsutako has been obsessed with Ii Azami for 20 years. While stalking him one day, she encounters Ii Azami being hit by a car. When she discovers he has lost his memory as a result of the accident, she decides to claim they are lovers in order to fulfil her lifelong desire. As a result, as Tsutako repeatedly lies one after another they begin to increasingly escalate…

two develop a loving relationship in spite of the emptiness she feels after losing her family.

they try to figure out how to live their lives

father-daughter

A high-school student (Kim Mu-yeol) awakens desire in Lee Juk-Yo (Park Hae-il), a 70-year-old poet, and in his pupil, who is 30.

In both movies there are dysfunctional teenage girls that causes problems to their surroundings. Both are rather slow paced and and not an easy watch.
However, there is no romance in Gaichu and it's set around a school.

Sakuragi Shun is a salesman who works for a Sunbath Home Housing, a house manufacturing company. He enjoys a happy life at home with his wife and daughter. Due to a sudden personnel change, he was assigned to transfer to Kagoshima, a city he was familiar with from his junior high school days. There, for the first time in 17 years, he is reunited with his first love Takeda Hana. She works as a junior high school teacher, while her husband who works as first mate, spends most of the year at sea, so she usually lives alone. While reminiscing the bittersweet memories of their high school days together, a hidden Pandora's box begins to open...

Furthermore, sparks also fly with Katoyama Naoya, Shun's friend and former love rival from their junior high school days, who now works for another company in the same industry. Although Shun has a beloved wife, the flames of jealousy quietly flare up. Meanwhile, Sakuragi Shun's wife is trying to suppress her anxiety. Based on their phone calls and emails, she becomes suspicious that her husband is cheating on her, and in order to eliminate her fears, she takes a trip to visit him in Kagoshima. As the slight lies begin to pile up, the truth becomes complicated, and when the lies are exposed, how will the relationship between the four of them
change?

Both films are set in Hokkaido
Both films are about an orphaned girl adopted by an adult male. They fall in love and but the love is forbidden since they are supposed to be a father and daughter.

Both are very disturbing where an older character is living with an underage school student and having sexual relations with, both give off the same feel and are very taboo