.It was the middle of the night when it happened. Konoha was attacked by the Kyubi. Minato chased after the culprit Uchiha without any result. Suddenly the Kyubi was out of the mysterious ninja's genjutsu. But it continued to ravage and raze Konoha. Then Minato ran to the anbu and commanded them to save the dying Kushina while he ran to seal the Kyubi, which was rushing towards Kushina and the kids.
'It's show time ' The reaper thought as he opened his eyes and broke through the spiritual realm and broke the plane and entered the mortal realm. He was finally summoned again and could take the possession of another soul. But there were children and were 4 in number. The eldest being a 2 year old brown boy and next to him were 1 year old twin blonde girls. The Yondaime held baby Naruto in his arms and commanded the reaper to seal the Kyubi into 4 parts and send each of them into his children.
The reaper nodded and held Minato's soul and sealed the Kyubi into the youngest siblings first. The children started growing whiskers as they were affected by the nine tails chakra. And when he moved to rei, the 2 year old kid, he noticed something strange. The boy had 2 souls. One weakened and the other a normal one. He sealed the Kyubi into the boy and noticed a strange phenomenon(fancy words, or is it?). The Kyubi was devoured by the weakened soul, Which then proceeded to merge with the younger soul.(the soul sf the Kyubi was devoured by Indrara as the Kyubi was significantly weaker than it was in the canon Naruto and was also weakened by the ritual, resulting in the devouring. Logic behind the knowledge. This is a fan fiction, so please don't be a biach and say 'It is non existent; this information is wrong; etc. )
The reaper who was shocked, hadn't noticed that he had increase the strength on Minato's soul and literally tore it. Minato had passed out (knocked out, not killed) and the hand seal was broken, causing the reaper to go back into the spiritual plane. ' Fu*k he escaped '. The reaper thought in frustration. Usually when a soul was killed in combat or passed through death, he was responsible to guide them into heaven or hell based on the purity of soul and their resolution, which usually was good or bad, based on the intention and was granted a small part of their soul as a reward for his effort. [ Bullsh*t no jutsu that you can ignore]
But when someone used his death seal, they left a bigger part of their souls behind, one that had more memories and energy he could use for himself. And it even contained emotion, which is the reaper's favorite food. They were absolutely delicious and helped make him way stronger as well and was a rather rare cultivation resource. 'I hate that I lost a soul but with that otsutsuki kid, he could gain a lot more energy as he was sure there would be many souls reaching his plane, sooner or later' . An otsutsuki is considered good luck by the reaper as they brought a ton of souls to him.
He then checked his black tablet and saw the name Kushina f**ing Uzumaki disappear, meaning she was saved before he could reap her soul. He absolutely hated medical ninjas and had even argued with God to reduce the talents of medical ninjas and make them very rare. 'Screw your family .I curse you and that mortal named Kushina to die a dirty death' cursed the reaper as thunder shook through the mortal realm, as in Author-Sama had graciously accepted his request or in this case, curse. But the real reason that the curse succeeded was because of the dirty deeds author made them do.