Ogata Yasuko and her three brothers sleeping in the name of a river

Yasuko was taken care of by her three nephews while her sister and wife went on a trip. Both of them were in love with each other since they were little, as they used to be. Of course, everyone sleeps in the river. However, Yasuko woke up late at night and was surprised by the major changes. All three of them were growing into "the Great Root." Taiko who thinks that she is a heir, but does not like her, secretly compares one and two cocks to each other. And I was jealous of one of my choices, but part of it was seen in a flat.