Prince Hours

This is sort of a standalone sequel/remake of the Korean of Princess Hours, which, this Thai version is a remake of.

The two male leads have a thing for the Main female lead. However the Female lead has someone in her heart.
Just like boys for flowers the love triangle exists.

It s a mix of boys over flowers and the parent story Goong.

Both female leads are married off due to the promises made by the grandfather to an old friend.