Lately, Kayo Fujikawa has been exhibiting peculiar behavior, causing her club colleagues Ayame Seki and Shiina Murakami to become concerned about her well-being. As her upcoming birthday approaches, Ayame and Shiina take on the responsibility of lifting Kayo's spirits to ensure that she has a memorable celebration. This additional chapter of Stella no Mahou takes place before Tamaki Honda becomes a member of the SNS club and showcases the growth of friendship amongst the senior members.