Otona ni NutsInstant Teen: Just add Nuts; Nuts Panic

From Tokyopop: Natsumi Kawashima, an energetic fifth-grader, is obsessed with her fantasy of being the ideal, sexy woman. Rejected at every advance by the cute guys that she fawns over, she finally gets a break when she picks up a package of mysterious pink nuts that are adults only. Eating these nuts causes her to morph into a voluptuous adult, and she's offered modeling opportunities and suddenly becomes noticed by guys who wouldn't have given her the time of day before. But, she's still a kid inside and is about to learn that things don't always work out exactly as you hope they will...