I love the idea of a separation wall with an inbuilt fire which creates a feeling of warmth throughout especially against the light, soft grey paint. It adds in a subtle way element fire to the white-grey (metal element) interior.
Would be fun kid hideout space! Awesome dog kennel under the stairs design idea. If you want an indoor dog house, utilizing the space under the stairs for a cozy, attractive and practical space for dogs is a good idea! I love this design.
Your standard bookcase-as-door secret room There’s added personality injected into a space when you’ve got a secret door or secret room. And it helps if that door doubles as a place to keep your books, too.