Mizuto and Yume used to date, but now they've suddenly become stepsiblings. Both of them agree that they don't want to do anything that'd disappoint their newly remarried parents. However, neither of them can accept the other as being the eldest sibling in the relationship. So they both agree to settle the matter with a game. Whoever does something in conflict with what people might consider normal sibling behavior, loses. Making them the younger sibling.
Sorry for having a brother complex.
.آسفة لأنّ لديّ عقدة أخ
Sorry, dass ich so einen
Bruderkomplex hab.
Pero le tengo mucho cariño, lo siento.
Pero le tengo mucho cariño, lo siento.
C’est plus fort que moi,
je l’aime un peu trop.
Mi spiace, ma che posso dire?
Ho proprio un debole per mio fratello.
Desculpem se adoro tanto meu irmão.
Вы уж простите
мою любовь к брату.