Nisekoi: False Love, Volume 14: Big Sister

Raku unexpectedly reunites with Yui Kanakura, a childhood friend who was like an older sister to him back in the day. Yui is now the head of a Chinese mafia syndicate, and not only will she be living with Raku while in Japan, but she's also his new homeroom teacher! Perhaps she can help Raku remember his past with Chitoge, Onodera and Marika…