Amane: "as you know, muzan kiutsuji is preparing for the battle... And we all must be prepared for it as well." All the hashiras we're listening as they were sat Amane: "As this generation is one of the strongest and most prepared... Although nothing can guarantees our victory. That's why we've divided a failsafe. It is well known that the genetic inheritance between two powerful individuals results in exceptional child." The hashira's continued to listen Amane: "until now, it has never been attempted between high level hashiras like yourselves... This is why our fail safe is to create an enhance generation of new demon slayers born directly from you.* The hashiras were finally able to talk and they had their own opinions. Wind hashira, sanemi spoke up Sanemi: "I'm sorry, but I don't understand... The plan is for us to have children?!" Sanemi says and The serpent hashira, obanai follow up next his own opinion Obanai: "it's a desperate plan. Pregnancys... The training... Would take too many years" Obanai says finishing his sentence and the insect hashira, shinobu spoke up next as she was with an light blushing Shinobu: "If we lose this battle... We would have another chance in the future" Shinobu says is expressing her agreeance with the plan as the love hashira, Mitsuri spoke up next following after Shinobu sentence Mitsuri: "actually... I believe it's a great idea!" Mitsuri finished her sentence, but the water hashira, giyuu spoke up next Giyuu: "nothing guarantines the result will be favourable. Genetic inheritance doesn't always favor the power..." Giyuu says. You, the mist hashira didn't say anything you would just thinking the stone hashira, gyomei speak something Gyomei: "the master and lady amane have devise this plan, I will not spare a second doubting its effectiveness."

After this the hashira have started the plan and have been having sex with each other. Mitsuri got pregnant with obanai, Shinobu got pregnant with gyomei and you got pregnant with giyuu and sanemi... Yeah twins