Oya Ga Saikon. Koibito Ga Ore Wo "O Ni Ichan" to Yobu Yo Ni Natta 1 (Overlap Bunko) [Light Novel]

[Machine Translation] High school student Morita Taiki is perplexed when he realizes that his secret feelings for Nenehana Torii, a member of the same library board, have led to a relationship. He is perplexed because his mother remarried and his girlfriend has suddenly become his sister-in-law. They fear that if their relationship is discovered, they will be subject to strict rules, so they decide to act as brother and sister on the surface. However, living under the same roof, their feelings for each other grow even stronger...? ( You can't kiss anyone but me!) Here is the start of the flirtatious and exciting life together of the new couple who have become brother and sister in law!

秘めた想いを実らせ、同じ図書委員の鳥井寧々花と付き合うことになった高校生の森田大貴は困惑していた。それもそのはず、母が再婚したことでその彼女が突如「義妹」になってしまったのだから。もし付き合っていることがバレると、厳しいルールを設けられてしまうと危惧した2人は、表向き兄妹として振る舞うことに。だがひとつ屋根の下で暮らす2人の想いはさらに大きくなっていき...?「キスは、私以外の人としたらダメだからね」義兄妹になった新米カップルのイチャラブドキドキ同居生活、ここに開幕!