Marmalade Boy

University student, Takatsuki Minato, likes things to be clean and in order while her stepbrother, Takatsuki Toru, is a bit of a player. One day, while cosplaying as a high-school student in a fashionable district in Tokyo, Minato accidentally bumps into Toru and quickly lies about her identity. To her surprise, Toru appears to take an interest in her alternate identity, Mina, and asks her out. Thinking that she might be able to cure Toru out of his playboy ways, Minato continues to disguise herself as Mina but will she be able to keep up the charade when she starts developing feelings for Toru?

Koishikawa Miki, a high school student, is told by her parents that they are getting a divorce and swapping partners with another couple. The other couple have a son called Yu, whom Miki becomes attracted to after moving in together.

~~ Adapted from the manga series "Mamaredo Boi" by Yoshizumi Wataru

Zhang Jing Yi is the FL in both. The chemistry is natural. The relationship had depth. However, BEITD does not have a satisfactory ending.

Both are about the growing romantic relationship between non blood related siblings (step vs. adopted). Both are set in school.

Both dramas have a theme of unconventional family, in Marmalade Boy they swap partners while in the other one they have partners of same sex.

Koishikawa Miki, a high school student, is told by her parents that they are getting a divorce and swapping partners with another couple. The other couple have a son called Yu, whom Miki becomes attracted to after moving in together.

"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