The line running down its side can store sunlight. It shines vividly at night.
It absorbs sunlight with the pink areas of its skin, which then shine. This appears to be a form of camouflage.
What a gorgeous sight this Pokémon is as it swims with its long, pink-painted caudal fins fluttering behind it. Finneon’s beautiful appearance has led to its nickname: “finery fish. ”