Lack of care and concern made Geoffrey wear one of his suits and a simple silver masquerade mask. He escorts Demelza to the dance and tones down the flirting with other girls out of respect for his date (But don't worry, he'll go back to his normal Geoffrey ways afterwards)
He also doesn't particularly care for the Weird Sisters but it doesn't mean he doesn't enjoy the live music. As promised, he saves a dance for Fliss and a few other girls if they were to ask.