Romilda Vane is a Gryffindor in the year below Ginny Weasley, so is in her fourth year when she is first introduced in The Half-Blood Prince . Romilda has developed a huge crush on Harry Potter. Romilda gives Harry candies, rum cauldrons, that are laced with a love potion. The candies are set aside and stored in a chest and find their way into the hands of Ron Weasley, who then consumes them. Ron immediately falls in love with Romilda, and Harry must seek out Slughorn for a cure, which leads to Ron being poisoned, almost dying, ending up in the school hospital, and breaking up with Lavender Brown.