"Heroes...?" Maru blinked at this. He remember once, in a moment of weakness, telling Mahiru that he wanted to be a hero. That he wanted to be better than what he was made to be... He believed he was a monster and his siblings were also monsters, created by a monster.

He heaved a heavy sigh.

"... So we're on a train... In the middle of nowhere... Flying off to save worlds? Is that what you're saying? ... Am I in an Isekai?" Maru blinked at her, puzzled by the whole thing. Pulled from his world to go and save another. It was definitely an isekai.