Domestic Girlfriend is a Japanese manga series written and illustrated by Kei Sasuga.

It started serialization in Kodansha's Weekly Shounen Magazine from 2014 to 2020, with its chapters collected in 28 separate volumes. As of April 2020, the manga had over 3 million copies in circulation, worldwide.

An anime television series adaptation was also produced, consisting of 12 episodes.

The chapter begins with Natsuo and Rui, having sex. After the sex, Rui and Natsuo do not exchange numbers, as Rui doesn’t want to be In a relationship.

Natsuo runs over to his best friend, Fumiya and tells him everything. Fumiya strangles Natsuo for having sex with a stranger, when he already has a crush on his school teacher, Hina.

Natsuo then tells Fumiya the whole story. He explains that how his friend invited him to a mixer. One of the girls at the mixer, Rui, was acting very strange. She was showing no interest in the mixer, Natsuo sees her alone and asks her why she was acting like that. She replies by saying that this is how she normally is.

They both then decide to leave the mixer. Rui takes Natuo to her home, she brings him in her room and asks him to have sex with her. Natsuo is stunned, he asks why, to which she replies, “I don’t want anyone to treat me like a child again”. And that is how they end up having sex.

The next day, while Natsuo is writing his novel on the school roof, Hina shows up and they talk for a while. Hina teases Natsuo about liking her.

The next day, when Natsuo comes to the roof, he sees Hina crying and asks her the reason, but Hina tells him that he is too young to understand adult problems. This angers Natsuo as he wants to help Hina and he ends up saying something rude.

As Natsuo is laying on his bed, depressed about what happened with Hina, his father comes in and tells him that he has decided to get married again. Natsuo doesn’t really have a problem with that, his father then tells him that the woman he is marrying is coming to meet them with her two kids.

Natsuo goes to receive her at the door, that is when he sees Rui and Hina with her.

What will happen, now that Natsuo’s crush and the girl he lost his virginity to, are going to become his step-sisters?