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Child-making SEX with a maid who looks like an older sister and a wife who looks like a younger sister ~ Collaborative work of love with 3 people!? ~

“How about I “help two people have sex”?”
A child-making life where a maid squeezes you until just before ejaculation!?
--Kyosuke and Tsubasa are told by their father that if they can have a child, he will allow them to have a child together.
Tsubasa, however, is too weak to endure sex,
Tsukiko (Tsuki-sis), a maid who is like a big sister to him, offers her support,
So the three of them began a life of procreation together.
Every day, Tsukiko would give Tsubasa a hand job, and he would cum inside her,
But when Kyosuke's handjob was no longer enough for him, he asked Tsukiko to cum until he felt like it,
But when Kyosuke's handjob wasn't enough, Tsubasa said, "Why don't you fuck your sister Tsukiko until you want to ejaculate?" Tsubasa suggested...?