Nothing is known about her past except the fact that she worked as a waitress before marrying Iemitsu.
Nana first appeared finding out about Reborn's letter of being a home tutor. She's often being seen cooking and running errands for the family. Reborn, Bianchi, Lambo, I-Pin, Futa, and Dino call her Mama.
Nana is oblivious about Tsuna and his friends' fight with the Varia and is seen to be very happy after her husband, Iemitsu comes home. She stays at the hospital where Lambo is charged after the Lightning Ring Battle, worrying over Lambo's condition.
In the Future Arc, she was revealed to be on vacation with her husband in Italy when the Millefiore Famiglia attacked the Vongola Headquarters; her condition in the Future was unknown after that.
Nana is first seen reprimanding Tsuna for stating to his father Iemitsu that whenever he came home, things got weird. Nana then goes on to meet with Iemitsu's CEDEF subordinates, whom he introduces as his "fellow workers" when digging for oil, also happily agreeing to let them stay at their house. When Byakuran arrives and flies up to Tsuna's balcony on the second floor, Nana remains oblivious and wonders if it was a magic trick. When the Vindice attacked team Colonnello at Tsuna's house, Nana came out telling Iemitsu that he would disturb the neighbors with the noise he was making. The Vindice then attacked her. She eventually makes a full recovery and her memories are erased, making her think the attack was a dream.