Vitamin Z: Welcome our New Supplement Boys

Vitamin Z is the sequel to Vitamin X, taking place after the events of the previous game. Former protagonist Yuri Minami leaves the school to study abroad, and her position of teaching the infamous Class X (now known as Class Z) is taken by new teacher Manami Kitamori. Manami, having just graduated college, is eager for the job until she learns of the A4 (Aho 4): the four most troublesome students of Class Z who refuse to take school seriously. The A4 is made up of the wealthy Tenjuro Narumiya, who loves to surf and is intent on finding his future wife, but despises studying; Chisato Fuwa, the best friend of Tenjuro who is focused on protecting him due to a bond between their families, but has trouble arriving to school on time for extra lessons; Yakumo Tachibana, a short boy who lives a double life as an idol in a boy band, and refuses to put in the effort required for good grades; and the perverted Arata Mine, a gifted tennis player who would rather put his time into building a harem of girls than studying. As in the predecessor, Manami must choose a student to tutor and then collect a combination of Love points (by letting their mistakes pass) and Study points (by correcting their mistakes) in order to obtain the best of a possible three endings. The B6 (Baka 6) make a return as teachers, with one assigned to each student in order to aid Manami in handling them.

Alternatively, Manami can choose one of the P2 (2 Princes) of the student council to help her deal with the A4. Kei Hōjō and Nachi Hōjō are twin brothers who are devoted to their jobs and each other. Like the A4, they also have three endings each.