JESS: I was attacked by a swan. Okay, you happy? A stupid swan.
LUKE: Now, how ’bout the real story?
Luke professes disbelief that Jess’ black eye came from a swan attack. Swans are notoriously aggressive during breeding season, and can do some damage when provoked – generally of the bruising variety, rather than breaking bones or anything. Breeding season is April to June, and this is February, but if you’re unlucky, swans can attack at any time.
I’m not sure why Luke doesn’t believe Jess at first, nor why Jess is too embarrassed to tell Rory the truth. For that matter, why is everyone so sure that Dean gave Jess the black eye? Had it happened before? Does Dean seem that dangerous? And if she believes Dean did hurt Jess, why is Rory angry at Jess, rather than Dean?
An interesting point to ponder: most swan-related injuries actually occur when the person is running away from the swan – falling over and cutting their knee, or getting a branch in their eye running through trees. (In one unfortunate case, drowning while trying to escape). Is it possible that this is really how Jess got a black eye, and is this why he is so embarrassed?