Yuji is crying because he's the one who kidnapped lana. He's not the only one who's crying, though. The reaper is also crying. He tells us that the only people who live forever are those who love their dead loved ones and realize that they'll never see them again. That's why they're taking their loved ones to the underworld to reincarnate so they can live again. Yuji says that killing someone who has decided to live in the underworld isn't the same as killing a person who has made the decision to live by