In both dramas, the lead girls have inferior looks, but end up falling in love. Many obstacles abound in their journey.
Busu no Hitomi ni Koishiteru (2006)
Similars
This is the 2019 remake of the same drama. This drama also has a handsome leading man falling in love with a supposedly ugly girl when in reality she's just a little over weight. I just love how sweet he is to her. One of the best leading men I have seen in a Japanese drama. Well worth watching.
In both dramas the ML is dating a beautiful model but cant help being attracted to a woman who is considered as ugly.