He doesn't get the chance: Miia takes and uses the Note.

Before Kimihito could even finish his first word, Miia shot forward, and snatched the Note from him. His eyes widened, and she asked, "Darling, what is this?" She began to read it.

"Hey, give it back!" he protested, but she wrapped him up in her tail again as her interest piqued.

"Whoah... A magic notebook? This is what hit you in the head earlier huh?" she asked, reading it over, her mind racing. She could use this to get Kimihito to lose all of his restraints, and allow them to have all the fun they wanted... But then there was that stupid law... They would have to avoid getting caught, and she thought she might have an idea with that...

She proceeded to take the pen from him as well as he comically struggled, and wrote, "Smith Kuroko will decide not to enforce the law against sexual relationships between monsters and humans, and in fact do all she can to help Kimihito Kurusu and Miia get away with having one, from running what interference she can without tipping anyone off, to warning Kimihito and Miia when they risk getting caught. Furthermore, Kimihito will no longer restrain himself with Miia, and freely use the Note on her however he pleased, with the exception of some more **** kinks like vomiting, scat, or gore." Even though she wanted Kimihito in a sexual way, there were some lines she didn't want to cross, and she found the idea of him using the Note on her quite appealing.

Once she felt the Note had taken effect, she released Kimihito, and gave him the Note and pen back. "Dang it Miia, what did you do?" he asked as he read the entry, and raised an eyebrow. "Wait, how did you know Smith's last name?"

"I paid attention during the process, Darling," she cooed at him. "Now that we have ourselves a safety net... How about we dispense with the restraining, and finally start to enjoy ourselves?"

Kimihito stared at Miia as she took an alluring posture, inviting him to use the Sex Note on her, and take her. He gulped slightly, knowing there was still a chance they could get caught... But thanks to the Note, he didn't care enough any more to not get into it.