Scorpius
Part Veela or not he should stay true to his family name and values and stay the fuck away from her. There are not many of the pure bloodline left, and those of us who were given that birthright need to do all that we can to preserve it. A Weasley, whether pure or not is still what they are Weasleys. They are known in the wizarding community as bloodtraitors! Malfoys, or any of us more noble families, do not associate with them.
I say do what it takes to make sure they don't end up together. If all else fails and he is determined to taint himself with her, I say just dis-communicate with him, no matter how hard that will be for you.