Samejima is the "cowboy cop" archetype. His partner is ALSO a cowboy cop, and also literally a dolphin. Said dolphin is the guardian of a girl who has unclear, ocean-related superpowers. Silliness ensues.
I like Samejima because despite being the archetype he is, he isn't stupid. He's also the one to play the straight man and comment on all the weird goings-on. The series is peak Japanese humor... I understand why it wouldn't land with some people, because Japanese-style humor isn't for everyone, but I thinks it's pretty funny so far. This series definitely deserves more love!