I've noticed a big shift lately where a lot of the traditional fan-translation sites for romance novels are getting super cautious about hosting full, explicit texts due to takedown notices. The legal landscape is just tighter now. What's filled that gap, in my view, are subscription platforms like Inkitt or Radish that use a freemium model. They have tons of spicy original stories, and you can read a decent chunk for free by watching ads or waiting for daily unlocks. It's not instantaneous full access, but the content is curated and the authors get a cut, which feels more sustainable than some random aggregator site.
I'd also really suggest looking at serialized fiction apps. Webnovel and Dreame have massive libraries sorted by tropes—enemies to lovers, dark romance, omegaverse. The free access usually means you get the first 30-70 chapters free before hitting a paywall, but that's often enough to know if you like the author's style and heat level. The comments sections are half the entertainment, too; you see real-time reactions to the steamy scenes which adds a community layer you don't get from a static ebook file.
Don't sleep on the official samples from major retailers either. Amazon's 'Look Inside' feature for Kindle books often includes chapters that are surprisingly… revealing. It's a legal peek. And some indie authors publish their steamier short stories or first-in-series permanently free on platforms like Smashwords to hook readers. You have to dig a bit with search filters, but the content is there, legit, and often quite bold.