Natsu no Arashi!

Season 1, Episode 9: Now's the Time for You to Become a Hero!

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At the Ark Coffee Shop, the owner makes a special request to everyone. She asks them to travel back into time and bring back non-expired mackerel sushi so that she can eat it. Kaya strongly opposes to such a ridiculous request, while Jun states that if you have the ability to go back you can essentially do anything. This causes a huge debate on the ethics of time travel and changing history and if they were to jump back to an altered reality...