If the guy is romantically interested in you, and you have no interest in him, he will never fully accept you denying interest in him unless you get nasty about it.
The problem is you probably like the guy as a friend, so you try and let him down easy. So you end up being nice to him as you tell him “not interested”… and as your actions are nice, the words don’t matter and you end up unwittingly giving him a Indicator of Interest in him.
So he continues to pursue you, thinking you’re potentially interested in him and he just has to try harder.
Look I’ve been there just like everyone else has been at some point. A plain and simple “look just fuck off” stings like hell in the moment, but at least you get the message and move on looking for a new romantic possibility. But a too nice letdown can keep you hooked in to being their orbiter for months or years more.
So if you’re the guy reading this, and you absolutely do not want to be “just friends” with a woman, and she knows that, then you have to see the offer for what it really amounts to. “Let’s just have you be my Beta Orbiter”.
In the end, a harsh “no” can be kinder than a gentle one. Sometimes you’re the one that has to tell yourself the harsh “no”, and move on from the offer of LJBF. Don’t waste your time with someone that doesn’t want you like you want them.
Don’t make someone else your priority, when you are only an option to them.