Is it a niche and specific situation, or do you want it to be? Generally, it's better to assume you're the rule and not the exception. What exactly is a 17 year old going to get out of a relationship with someone so young that any slight mistake could put him on a sex offenders register? That's a big risk to take with somebody, and I don't think a 17 year old is capable of making that kind of decision. And it won't be up to you to decide what's too far, if someone reports any kind of inappropriate contact he'll face charges, even if you consented. Even if he's a good fella in an unorthodox situation, and it's the exception and not the rule, one wrong move and he's fucked his whole life. If you really love each other you can wait a few years to date, and you won't put him at risk. It's easy to agree to no sexual contact now, but when you're in the situation and you both want it, it's a lot harder to resist. Also grooming you for a sexual relationship in the future is also illegal. So having conversations and starting a relationship with you with the intent of having sex once you turn 17/18 is also against the law as far as I'm aware. If you really love him, you'll let him live his life without jeopardizing his future, and if he loves you he'll understand that and not want to put you in a situation that could potentially cause you trauma