The Casanova is one of the easiest weapons to use when it comes to unlocking its full potential quickly.
Loves and friends are not retroactive when this sword is equipped, you must gain new loves and friends each time or cause people to dislike the hero and then regain their love and friendship repeatedly.
Prior to Balverines appearing in Mistpeak Valley, Brightwall makes an excellent location for gathering friends and love interests. You never have to travel far or fight very hard to reach fetch and courier locations, nor do you have to travel far to reach date locations (Brightwall Academy Gardens and Brightwall Bridge are often used).
There seems to be a glitch in the unpatched version of the game, where when undergoing A Marriage of Inconvenience, when seducing Veronica shortly before she wants the wedding ring it instantly completes the Charmer and Beloved augments. This does not occur with the female version of the quest which requires seducing the husband instead.