X - Marks the spot. It is such a cleaver hide-out, any attempt at humor will go unnoticed.
By the way, the the original building, a loft, may well be cozy. Not clear from photograph.
Disclaimer: Mark Twain (1835-1910-To be continued) is unlicensed. His river pilot's license went delinquent in 1862. Caution advised. Daily Paul ☑