Nao

Nao is a shy and sweet single mother. She is divorced from an alcoholic and verbally abusive husband. Together with her son, she leads a modest life working as a waitress and making clothes for fun for herself and her kid. She dreams of one day opening her own cafe, wishing dearly for it to be water themed as her son, Renji, is in love with the ocean and wants to become a marine biologist.

She and her kid often goes to the aquarium, and always attends without fail when Kuugo Sakamata is holding a lecture. Her son adores Gang Orca, and lights up during each and every lecture and comes back with more and more questions. It gets to the point where they will stay until the aquarium close, all the while Renji is excitedly talking to Kuugo who seems to love it as much as the kid does. One summer day, he asks if they should head out for an ice cream or something when the aquarium close, seeing as Renji still hasn't had his fill and is reluctant to leave. Nao is flustered and worried they are being a bother, but they end up going regardless and have a lot of fun.

Kuugo friends her on social media, and they exchange phone numbers - though they don't often talk. It isn't until the two are missing a lecture that he finds reason to message her - only to find out that the kid is sick and she's had a stressful day but regrets being unable to make it... he of course takes it upon himself to come visit them and bring along supplies. This is when her ex husband decides to drop by, and it takes Kuugo 'politely' asking him to leave for him to go, but by then Nao is already upset and more than a little scared. It is getting late, and Kuugo is reluctant to leave - just as Nao is reluctant to be alone. She timidly asks if he'd mind staying around just for the night, in case her ex comes back... and he agrees, making tea for the both of them as they sit down and talk about her ex. He fully intends on learning as much as he can to see if there's something the police can do about the situation.