A deadly virus known as "Algernon" has attacked humanity with vicious meaning. At the forefront of the battle is the mystifying Akamatsu Industries—disguised as a heavy machine factory in Tokyo, this undercover organization uses neural enhanced weapons known as NeuroNoids to battle Algernon. Also helping with their secret efforts is the mysterious mutant who is only known as "Betterman." (Source: ANN)

In the final years of the Bakumatsu era lived a legendary assassin known as Hitokiri Battousai. Feared as a merciless killer, he was unmatched throughout the country, but mysteriously disappeared at the peak of the Japanese Revolution. It has been ten peaceful years since then, but the very mention of Battousai still strikes terror into the hearts of war veterans. Unbeknownst to them, Battousai has abandoned his bloodstained lifestyle in an effort to repent for his sins, now living as Kenshin Himura, a wandering swordsman with a cheerful attitude and a strong will. Vowing never to kill again, Kenshin dedicates himself to protecting the weak. One day, he stumbles across Kaoru Kamiya at her kendo dojo, which is being threatened by an impostor claiming to be Battousai. After receiving help from Kenshin, Kaoru allows him to stay at the dojo, and so the former assassin temporarily ceases his travels. Rurouni Kenshin: Meiji Kenkaku Romantan tells the story of Kenshin as he strives to save those in need of saving. However, as enemies from both past and present begin to emerge, will the reformed killer be able to uphold his new ideals?

As Yumeko Jabami's fame grows and the reputation of the student council dwindles, Kirari Momobami decides to revolutionize the group. To this end, she announces an election for its next president. The rules are simple: each student in the school receives one chip. Whoever has the most chips by the end of thirty days becomes both the new president and the head of the Momobami clan. Upon receiving news of this development, the Momobami branch families spring into action. Eleven transfer students arrive at Hyakkao Private Academy, each aiming to lead both the school and the Momobami clan. Equipped with unique talents, they will compete to get as many chips as possible—but their chips are not the only things on the line. [Written by MAL Rewrite]

Unlike many schools, attending Hyakkaou Private Academy prepares students for their time in the real world. Since many of the students are the children of the richest people in the world, the academy has its quirks that separate it from all the others. By day, it is a normal school, educating its pupils in history, languages, and the like. But at night, it turns into a gambling den, educating them in the art of dealing with money and manipulating people. Money is power; those who come out on top in the games stand at the top of the school. Yumeko Jabami, a seemingly naive and beautiful transfer student, is ready to try her hand at Hyakkaou's special curriculum. Unlike the rest, she doesn't play to win, but for the thrill of the gamble, and her borderline insane way of gambling might just bring too many new cards to the table. [Written by MAL Rewrite]