Rowling revealed in a 2007 web chat that Hermione smells freshly mown grass, new parchment, spearmint toothpaste, and Ron’s hair. Amortentia, of course, reminds a person of the things they find most attractive.
And we all know how Hermione and Ron’s relationship ended up.
Their blood lines can be traced back to the Peverell family, but so can most wizarding families.