Yes. HUSH lists 38 adults-only houses in Spain, each one with a minimum age of 18 written into its own house rules. They include Legado Alcázar, Hotel Kivir, El Hotelito del Cotillo.

The 38 Spain houses on HUSH are in Seville, El Cotillo, Playa del Inglés, Casavells, Corralejo, Platja d'Aro among others.

One thing only: the house rules set a minimum age of 18 or higher — the rules a guest agrees to at check-in, whether they are on the hotel's own site or on its booking profile. It is not the booking site's adults-only tick-box, which the hotel sets itself, and it has nothing to do with adult content. Each page quotes the sentence and says where we read it.