Fearing that Lisa will grow up having no friends, Marge secretly paid Tumi to hangout with Lisa. Tumi met Lisa in gym, after Lisa had no partner to square dance with. As Tumi and Lisa hung out, Bart became suspicious of Lisa's new friend.
Bart would subsequently reveal the information to Lisa, through a folder containing pictures Bart took over the past few days, much to the shock of Lisa herself. Lisa would eventually confront her mother on why she was paying someone to be her friend.
Afterward, Lisa told Tumi they had to be honest with each other in order to stay friends. When Tumi revealed that she's not an actual vegetarian and eats raw horse, Lisa ran off.
Tumi was nice to Lisa, despite being paid to hangout with her. She and Lisa bonded well throughout the episode. It was also revealed that Lisa only sees Tumi during tornado drills, due to the fact Tumi is in the other second grade class.
She wears a light blue and magenta shirt, a purple and orange sweater over her shirt, a magenta skirt, long purple socks, and blue and white sneakers. She has black hair and wears a purple alice band with a flower. Unlike most characters, she has a pale skin complexion due to being Japanese.
- It's very possible Lisa has met Tumi before, since she states both of the second grade classes are together only during tornado drills.