Tania has a very muscular physique, about as muscular as Tyranno Kenzan (Tyranno Hassleberry in the English dub).
When Judaii Yuki (Jaden Yuki in the English dub) and the group face her, she had made most of the male students build an arena for her. She then duels Daichi on the condition that if he lost, not only would he surrender his Spirit Key, but he would have to become her boyfriend. Daichi does his best to defeat her but loses. His Spirit Key is lost to the Shadow Riders and his free will is lost to a small degree, becoming infatuated with Tania.
Judaii faces Tania to save Daichi. At this point, Tania had become bored with Daichi and broke up with him. Tania makes the same deal with Judaii, if he lost he would become her new boyfriend and his Spirit Key would belong to the Shadow Riders. Judaii is able to defeat her and she realizes she is not worthy of him. Her Shadow Charm loses power and her true form as a tigress is revealed. Bastion becomes free of her influence.
In the third season, Judaii and his group travel across 12 dimensions to rescue Johan Andersone (Jesse Anderson in English dub) and defeat Yubel, an evil Duel Monster Card. When they reach the first dimension, they meet with Tania who acts as their guide. It's shown Daichi and Tania still have feelings for each other. After the group save the town in the first dimension, Daichi stays with Tania to help the dimension after Jaden defeats Yubel.