After Jimmy Lemonstone fell out of the cruise ship by accident while Spike Pokaton is still on board, Jimmy drowned after getting caught by a Demon Moray Eel, but then Gwen saved Jimmy with her powerful water trident, summoning explosive bubbles to knock out the demon moray eel. Gwen takes Jimmy to her city where all Sea rock monsters live. Passing through the bubble gate, Gwen takes Jimmy to her famous house that she won in the arena contest and then gave Jimmy CPR.After the next day, Gwen told Jimmy how he got here and how she saved his life. Jimmy called his friends he's fine, and had a new friend who saved his life from drowning. Jimmy asked if Gwen would come with him in his huge quest about the rock monster's pasts. Gwen Accepted and join the journey with him!