Do you send messages using short intense replies, like “I want to rip off your clothes and fuck you like an animal”, but without going into the details of the environment, setting, etc.
Or a do you get descriptive and write out a shared fantasy as if you were both writing an erotic novel together, describing how you look, feel, what you do, what is happening in the world around you, etc. Example: “I notice you sitting there in the library, reading your book, and something animalistic awakens in me. There is something about that innocent pose that makes me want to rip you out of your peaceful little bubble. As I approach, I imagine bending you over the table, right here, right now. You are an animal too. I can sense it.”
I can be extremely descriptive and I often am, but I’ve never narrated masturbatory fantasy from the perspective of the first person in present tense, like you just did. You’re not going to give them the best orgasm anyone’s ever given them because you’re not literally, physically present. The best you’re ever gonna do, is make them give themselves the best orgasm they’ve ever given themselves, and you need to approach that directly and without trying to make it look like something. Stop pretending you’re not having this conversation over text and that you don’t intend for them to read your messages while masturbating. Don’t require the suspension of their disbelief; that’s never gonna happen; you’re not that good; you don’t have to be that good because no one is. Just tell them, directly, in exhaustive detail, precisely what you want to do to them in the most explicit way possible. Use euphemisms wherever it would be weird not to, but that’s it. Describe everything either word-for-word literally or exclusively through metaphor. You’re trying way too hard.