She came from the Dark Realm, looking for some kind of entertainment and adventure, and eventually came upon a small island to stay on. Whenever she's in the Light Realm, she swims around to try scare the living daylights out of anyone who comes by. (TRIBRID WEAKNESS) She tends to get headaches or feel light headed when she's out in the sun with no water for two long.
Thanks to @Pikakit for this amazing RP! (I did trace the original vaporeon didn't use it)