Mark has found a magical way that allows him to travel at night: his school bag becomes the flying vehicle that takes him wherever he wishes, and he experiences many adventures.

When he decides to visit a small planet, he meets two strange metallic creatures, Sen and Epi. The three of them head towards the city; there, Sen has to fulfill a peculiar mission, which greatly unsettles Mark when he learns about it.

Sen believes that he is human too because – like Mark – he has two hands, two feet, and two eyes. But is appearance what defines being human, or is it something else? Sen’s true nature will be revealed through his free will to make the right choice.

A groundbreaking, touching story that shows how real humans are not defined by their external features but by their choices, behaviors, and actions.