Stella is another character who evolves throughout the series, going from a stuck-up, jealous kind of-girlfriend to Sky who bullies Bloom, to actually becoming an ally. At first, she looks down upon Bloom, making her feel inferior in magic talents and fashion sense, while also being supremely jealous of the friendship she's growing with Sky. When Bloom loses Stella's gateway ring to a Burned One, she makes her go back and get it– while Bloom finds powerful fire-wielding abilities within her and kills the Burned One for the ring, Stella gets lost in the forest and her magic doesn't even work.
We also find out Stella is a princess and is the Queen's daughter. The ring was one of the crown jewels of Solaria. For this reason, she feels immense pressure, and is extremely guarded. Stella is emotional, Riv tells Bloom that Stella purposefully blinded her last roommate Ricki, who had flirted too much with Sky, but it was accidental and caused by her feelings. And she's also a bit evil – Stella tells Riv that Bloom is a changeling, which causes Sky to break things off with her for good in episode four. However, throughout the rest of the show, she redeems herself by helping the group defeat the Burned Ones, and being another source of support with her unique powers of photokinesis and making herself invisible.