Both series focus on a forbidden romance between family members. Mistu no Aji features a uncle and niece who have fallen in love while 90 Days of Love they are first cousins.
90 Days of Love (2006)
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Both titles focus on a romance between first cousins and how they navigate their feelings for each other.
Both have incest/taboo relationship.
90 Days of Love the main leads are cousins; while the Rose, there is half-siblings.
Both are very melodramatic, and I personally like The Rose better, but both are good for what they are.
"Newlyweds" Keiichi and Akira Hirose have moved to a new city. Keiichi, who works as an author, and Akira, who works with kindergartners, are hiding a big secret from the people around them.
~~ Adapted from the manga series "Saraba, Yoki Hi" by Akaneda Yuki