Swallowing cum can actually be the biggest sign of love, even bigger than “accidentally” forgetting to take the pill in order to guarantee the bond for life.
You can say what you want, but unless a girl has a swallowing fetish and loves to drink cum like others drink their milk for breakfast, it is a sign of attraction, affection and in some cases deep love. If she wouldn’t have those feelings for you, she wouldn’t do it.

Of course there are some girls who have a fetish or who absolutely love the taste of semen.