Tadashii Kodomo no Tsukurikata!

Tadashii Kodomo no Tsukurikata! (正しいコドモの作り方!) is a Japanese manga series written by Marita Morita and illustrated by Takayoshi Kuroda. It was serialized in Shogakukan's shōnen manga magazine Weekly Shōnen Sunday from April 2012 to September 2013, with its chapters collected in seven tankōbon volumes.

Synopsis
Yū Tanaka is an ordinary high school boy who has feelings for his classmate and childhood friend, Kyōko Takane, but feels he is no match for her because she is cute, good at sports, and popular in their class. One day, Yū is informed by Raito, an agent sent from the future to prevent the extinction of humanity, that his genes will destroy the future human race and Kyōko is the only one who can nullify his genes. In other words, if the two are united, the extinction of humanity can be avoided. To save humanity, Yū begins to approach Kyōko while resisting temptation from other girls, but Raito is not the only agent from the future.

Publication
Written by Marita Morita and illustrated by Takayoshi Kuroda, Tadashii Kodomo no Tsukurikata! was serialized in Shogakukan's shōnen manga magazine Weekly Shōnen Sunday from April 25, 2012, to September 18, 2013. Shogakukan collected its chapters in seven tankōbon volumes, released from November 16, 2012, to November 18, 2013.