The Witch Controls Her Age and Magic With a Kiss! summary:
Tooru Mugura is a boy so low-profile that even his family sometimes loses sight of him. One day, he encounters a witch. Since her true identity was found out by Tooru, the witch is cursed to lose half her magic, and she says that his most heartfelt wish must be granted in order for her to get her magical power back. And what's more, the thing necessary for her to restore her power every day is... a kiss?! A heart-pounding story starring the unlikely duo of an "invisible boy" and a witch! (Source: Kodansha, translated)