It's interesting from an existentialist point of view, but MC really is a character that goes along with what everyone else wants him to do in his pursuit of meaning. He chooses to impregnate his teacher because it's what she wants from him, he chooses to go to school in Tokyo, and, hell, he'll even commit suicide because someone suggested it to him. The only thing he does want for certain is to leave the town, even if it will cost him everything
People talk about spineless MCs, but I'm not sure if MC is so passive because none of it matters to him anymore or if the only things he wants is to get out of this town
Notice: he doesn't tell her that he wants to die, has attempted suicide, has slept with his teacher and the author's wife. He instead removes the mask, which is ironic because he's saying the confession is over, and so he can lie about not wanting to reveal anymore