Soft Rain or Another Story of Mowgli

Ласковый Дождь, или Еще одна повесть о Маугли

Also known as Laskovyy Dozhd', ili Yeshche odna povest' o Maugli

It's post-apocalyptic future. The group of boys does not realize that one of them is not quite a person... he's the "Mowgli Project". It is also unknown whether Mowgli himself knows about this.