Akari finds herself nervous coaching a new undine as a Prima, until she awakens to find that it is just a dream. To soothe her worries, Alicia recalls stories of her beginnings as a Prima, as well as the memories she made.
ある日、プリマになった夢を見た灯里は、いつもと違う日常風景に戸惑いを覚えます。食卓にアリシアの姿はなく、ドアを開けて入ってきたのは見知らぬ後輩。やがて訪れるであ...