Shy Away (トンダリヤ, or "Tondariya" in Japan) is a variety of Shy Guy that has the ability to fly. She first appeared in Super Mario Bros. 2 under the name Beezo, but this article concerns her appearance in Super Mario RPG: Legend of the Seven Stars only.
Shy Away live at Land's End, as well as Bean Valley. Although she command impressive magical abilities, Shy Away choose to run away from intruders instead of fighting them. Additionally, she now show a love of watering plants - she will often plant other monsters to fight for them in order to avoid battle.
Shy Away worked for Valentina during her reign in Nimbus Land. She was tasked with blocking the entrance to Nimbus Land, preventing any interference to Valentina's plan. Thus, Shy Away traveled to Bean Valley, growing a Smilax, effectively blocking the pipe leading to Nimbus Land. After Mario defeats the first Smilax, she reappears and grows two more. Eventually, she creates the Megasmilax, a gigantic Piranha Plant with magical abilities. Ultimately Mario prevails over the plant monster, thus causing Shy Away to run away (and accidentally drop her important Seed).
She retreats to Nimbus Land. Once there, she is ordered by Valentina to provide nutrients to Birdo. Mario meets up with Shy Away again, and the flying gardener tries to flee a second time. However, the door leading out of Birdo's room is locked, preventing Shy Away's escape. In fact, Birdo holds the key to the door. Thus Mario has to "play" with her (i.e. battle her) to receive the key and open the door.
Once Mario opens the door, Shy Away flies to the throne room, warning Valentina and Dodo of Mario's arrival. After warning her, she flees for a third time (and is followed by Valentina and Dodo, who also do not wish to fight).
Eventually Mario and company catch up with Valentina and Dodo. The villainous duo are then soundly defeated by the hero plumber and his allies. Afterwards, Mario can find Shy Away hiding on an invisible path off the edge of Nimbus Land. Hoping to avoid a fight, she gives Mario the Fertilizer and then runs away.
If Mario gives the Seed and Fertilizer to the Gardener in Rose Town, Mario will receive the Lazy Shell weapon, Mario's ultimate weapon, and the Lazy Shell armor, the best defensive armor in the game.