Tập 6: Bánh White Day của Souta biến thành Negatone, kích hoạt vũ khí mới của Hibiki

6

When Souta decides to make something for Kanade for White Day, Hibiki agrees to help him out in making a cake. However, Kanade yells at Souta for making a mess in the kitchen, causing him to become upset and run off, where he is trapped after Siren makes a Negatone out of his cake. As Kanade fights to reach Souta, Hibiki's desire to protect their sibling bonds grants her a new weapon. Afterwards, Kanade apologises to Souta and accepts the gift, only to find it is filled with wasabi. (Source: Wikipedia)