Osananajimi wo Shuuchaku Otoko ni Sodatete Shimaimashita

Erina, the only daughter of a huge merchant corporation, lost her voice completely after the shock of losing her mother, and her childhood friend Noel, whose growth has stopped due to a curse and who remains in the form of a boy. For 15 years, the two lived like a family, and Erina was only able to speak to Noel. One day, Erina, who believes in the superstition that "if you kiss a man of the opposite sex on the day before your 20th birthday, you will be happy for the rest of your life," kissed Noel, but the next day, Noel was in his adult form! This incident triggered Noel, who had originally had feelings for Erina, to grow even more obsessed with her...! "I wish she would choose me instead of the other man..." A status-disparity romance that begins with a kiss between a young lady who has never known true love and a secretary who can't stop doting on her! (Source: Comico, translated)