The masculine form of
Lucretia would be Lucretius, by Latin standards. I'm not sure if Lucretius was ever actually used though.
Lucas and
Lucretia have nothing to do with each other etymologically. They only share two beginning letters, that's all.
Miranda
Top 10 Reasons Why I Procrastinate:
1.
Proud adopter of 15 punctuation marks; see my profile for their names.