It is a homebuilt aerobatic biplane that has been around for a long time. Many have been built.
Here is a picture of one built by Gunnar Iversen of Norway
The Jungster Papoose RK1 was designed by Rim Kaminskas of Los Angeles, CA between 1957 and 1964. Rim is an aeronautical engineer. He designed it to be simple and strong. He based it on the Bucker Jungmeister.