A Japanese princess will lose her royal status — all because she fell in love with a commoner.

Princess Mako, 25, the eldest granddaughter of Emperor Akihito, must abdicate her lofty position when she marries Kei Komuro under imperial law, the BBC reported.

The princess and Komuro met in 2012 at a restaurant while studying at the International Christian University in Tokyo.

Now, the Imperial Household is planning for Mako’s engagement to Komuro, 25, which will only be made official after a ceremonial exchanging of gifts.

They’re expected to wed sometime next year.

“Now is not the time for me to comment but I want to speak at the right time,” said Komoru when asked about the engagement plans.

Mako’s resignation — as well as the possibility of Akihito, 83, abdicating due to old age — has reignited a decades-old debate over royal succession to the Chrysanthemum Throne.

But Mako won’t be the first princess to step down.

In 2005, her aunt, Princess Sayako, abdicated after she became the first-ever Japanese royal to marry a commoner.

Sayako, the only daughter of Akihito, had to learn how to drive, grocery shop by herself and buy furniture. She also had to downgrade from her palace digs to a modest one-bedroom apartment.

Japan is weighing whether to change a law that forbids an emperor from abdicating – but the law would still enforce males-only succession.

For that reason, there are only four heirs to the emperor’s throne — Akihito’s sons Crown Prince Naruhito, who is first in line, and Prince Fumihito, Prince Hisahito and Prince Masahito. Hisahito is Fumihito’s son and Masahito is the emperor’s younger brother.

“There is no change in our view to proceed with consideration of steps to ensure stable imperial succession,” Cabinet Secretary Yoshihide Suga told Reuters after news of Mako’s engagement broke.