Bicycle built for one and a half

I saw an interesting bicycle while riding the bus today. It was one of those bicycles built for two. While those are unusual, I have never seen one quite like this. The front half of the bike was clearly designed for an adult rider, but the back half appeared to be intended for someone much shorter. I’m not sure if the back half is intended for a child or just someone of shorter than usual stature since it only had a full-sized rider up front when I saw it. Certainly haven’t seen anything like that before, although I guess it doesn’t surprise me too much considering the assortment of other bicycle-like contraptions I’ve seen in this town.