When sixteen-year-old Lili Reed’s dad decides he needs “an adventure,” and his old friends the Takadas invite them to spend a semester in Japan, Lili is desperate enough to leave her carefully managed routine and give it a try. Because this has to work. Four years, five months, and twenty-one days ago, Lili learned you can lose everything in a single moment. That was the day her mom died. The day her dad started wrestling with depression. The day Lili learned she had to be the strong one, because her little sister Lennon needed her.

Tokyo turns out to be just the adventure Dad and six-year-old Lennon need: new sights, new sounds, new food, new friends, even a pretty, Japanese “lady friend” who keeps coming around. But for Lili, it’s too many new things at once. She doesn’t know how to eat with chopsticks. Navigate the trains. Discern “great mysteries” like which carton has milk and which has liquid yogurt—because she can’t freaking read. She can’t even use the high-tech toilets without getting doused by the bidet function. And why does Tai, the Takada’s seventeen-year-old son—whose crooked grin is way distracting—seem to be around for every one of her mishaps?

Even more unsettling, Tai seems intent on rekindling the friendship they had when they were kids. But that is so not happening. So what if he plays guitar (swoon!) and makes her laugh, reminding Lili of another version of herself—one she hasn’t seen in four years, five months, and twenty-one days. Because what good is it to risk her heart on something so easily lost in a single, tragic moment…like love?