Michiru finally gets to drink with Nao’s sister Makoto, who is closer in age and a third-year student in college weary of entering the labor market. After a morning of yelling at her sister for amassing so much recycling from beer cans and a day of studying and worrying, she needs a drink, and not just any drink: Kirin Hyoketsu (“Frozen”), a canned shochu-soda-fresh-squeezed juice blend she prefers to other chuhis.
After a couple years of listening to Nao’s lectures about the alcohol she’s consuming, Makoto has a knack for it too, and when talk turns to Makoto’s worries about getting a job, Michiru suggests the best way is to be straightforward and informative about the company she wants to get a job from, the same way she talks about booze.
When Nao comes home, she seems to have gotten the message and announces she won’t be drinking that night; just eating her TV dinner and going to bed. Makoto tells her she doesn’t have to kick drinking cold turkey like that, and Michiru urges her to be straight once more.
It’s not just that Makoto doesn’t like loud, personal space-invading drunks (she doesn’t), but she’s genuinely worried about her sister continuing on her pace of drinking. When Nao hears her sister doesn’t hate her, she decides to crack open one—and only one—Hyoketsu with her little sis.
When Michiru wakes up, she discovers the sisters never left the couch, but had a lot more than only one, since they were having so much fun. And since Nao has the day off after working overtime and Makoto doesn’t have classes that day, they have the whole day to recover from their sisterly celebrating.