Some antonyms for demure are:
Arrogant...That's all I have for now...Sorry!! :]
Im-modest
The aristocratic young lady was very demure and sophisticated, and acted very politely at the luncheon.
Jackie Kennedy was a beautiful first lady who was known for her understated , demure sense of style.
Despite her demure appearance, she is a competitive speed skater, always ready for a challenge on ice.
demurer, demurest
Antonyms
she gave him a demure smile
undisciplined could mean "wild", so 'tame' could apply undisciplined could mean "uncouth" or "uncultured", so 'demure' or 'genteel' could apply
The aristocratic young lady was very demure and sophisticated, and acted very politely at the luncheon.
On the wall was a painting of a demure Victorian girl. Although she was demure in public, she was wildly outgoing at private parties.
Demure means someone who is modest and reserved in manner or behavior. Modest, or shy.
Jackie Kennedy was a beautiful first lady who was known for her understated , demure sense of style.
Despite her demure appearance, she is a competitive speed skater, always ready for a challenge on ice.
Silent or serene.
Someone who is affectedly modest or shy may come across as insincere or overly self-deprecating in order to seek attention or portray humility in an exaggerated way. They might downplay their achievements or seek validation through their perceived lack of confidence.
The cast of Little Miss Demure - 1912 includes: Fred Rains as Uncle
Demure, Immure.
demurer, demurest