This place is very accessible to the Metro (Tirso de Molina). It's also a very short walk to other Metros (La Latina & Anton Martín). There is also a theatre nearby with some very impressive plays/musicals (they get packed in the evenings).
I am a vegetarian and I wanted to make my own meals. But I would advise against cooking at Daniel's place and to just eat out. Madrid is a food haven. There are lots of nice bars and restaurants. For those with dietary restrictions, you aren't that far away from vegetarian/vegan places (a few Metros away or if you are willing to walk).
The bed is very comfortable even during winter (with the heating off). Remember to tighten the faucets in the private bathroom, otherwise some water will leak.
Daniel is ready to respond to your queries. He also offered to hold your luggages while you go explore the neighborhood.
I haven't gotten to interact much with his cat, though I've been startled a few times because I was trying to get to the front door in the dark. Cat is friendly.
Do note that since the room is next to the kitchen, whatever that goes on in the kitchen is audible. Also, the room is furthest from the router (in living room) -- Wifi signal isn't as strong if you closed your door.