Youko brings Kantarou tea whenever he stays up late at night, and if she finds him asleep, she puts a blanket over his shoulders and douses his lamp. As long as she’s known him, he’s been obsessed with finding the oni-eating tengu, and sometimes she worries how this is effecting his health.
“A tengu can look as monstrous as he wishes,” she tells him once. “He may not be what you expect.”
Kantarou just smiles and shrugs. “I know,” he says. “I don’t care.”
Searching for the oni-eating tengu is his life’s work, and possibly all he will leave behind. Everything else — the things he does to earn the money for them to survive, that’s all just side jobs to pay the bills.