What does Lucy find comforting about Mr. Tumnus's home?

In the Lion, the Witch and the Wardrobe, Lucy falls in love with Mr. Tumnus's home as soon as she walks through the door. As Lewis states,

Lucy thought she had never been in a nicer place.

Through Lucy's eyes the author writes,

It was a little dry, clean cave of reddish stone with a carpet on the floor and two little chairs ("one for me and one for a friend," said Mr. Tumnus) and a table and a dresser and a mantlepiece over the fire and above that a picture of an old Faun with a grey beard. In one corner there was a door which Lucy thought must lead to Mr. Tumnus' bedroom, and on one wall was a shelf full of books.

What probably makes it most comforting, however, is that the whole scenario, from meeting the faun to having tea with him, resembles a beautiful, nonthreatening fairy tale. The faun is so frightened when he sees Lucy that he drops all his parcels. He then shows he is the perfect gentleman by holding an umbrella over Lucy as they walk to his house. When they enter his home, the Faun lights a little lantern and throws a log onto the fire, and Lucy is "blinking into the light of a wood fire."
It is not until Mr. Tumnus admits that he is a kidnapper that the atmosphere changes and Lucy becomes desperate to get home. Suddenly, Narnia is a dark, dangerous place "full of [the White Witch's] spies."

The journey back was not at all like the journey to the Faun's cave; they stole along as quickly as they could, without speaking a word, and Mr. Tumnus kept to the darkest places.