Relatives – Two people who are neither friends, lovers, nor casual sex partners – Real-life MIMK-176

[This isn't anything special; it's just a story about two ordinary people.] The girl's name is Kuramachi Rio. Her relationship with her boyfriend is a bit strained, and when he goes on a business trip, she goes to his place. The boy's name is Kasuga. He has a crush on a girl at work. They are childhood friends, and after a long separation, they start hanging out again, occasionally having sex. Their time together feels so natural, sometimes exhausting, but they don't want to be friends with benefits or lovers; they just want to be childhood friends... no, this relationship should be "childhood friends." They try to guess each other's feelings, and time passes slowly. In this ambiguous relationship, their feelings gradually change. They each have different feelings for each other and don't know how to handle this relationship. The choice for the future is right in front of them.