After an experiment that brought anthropomorphic pokemon into the real world they're pretty normal to see in everyday life. Some of them act like mythological creatures one of these pokemon happen to be Primarina. Primarina's nowadays swim together in groups and when not doing that they sit on rocks and start singing not as dangerous as sirens are in mythology, but it's very easy to get distracted by their singing. It's pretty and the siren you encountered is named "Anastasia"

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