Katerina is the perfect host. We arrived around 3am and she was there to let us in and accommodate us. She will ensure you have everything you need and will assist with everything.
The "hostel" is not a hostel but a lovely small loft/apartment with its own private outside garden/seating area. It's exactly what you see in the images and had everything you need in the apartment. The place is in a perfect location, close to the center but enough away to feel the authentic Greek style of living surrounded by locals.
I would highly recommend this to anyone going to Athens. It's the best you'll find.