"I've never gotten a sword or shield. But if you want to see the rifle, you could come by and take a look at it."

She's so eager to show off her gun that she's completely forgotten that this same invitation was what led her to kissing that waitress, and that she's told Clara that story.

Of course, her invitation at the time hadn't had any guile or ulterior motive behind it - she really had just wanted to show off her guns, and one thing had led to another. There's no guile or ulterior motive here either, no sneaky intent to turn 'come look at my gun' into a snogging session. Especially as all of her thoughts are completely preoccupied with Vi. She really is just excited to show off her rifle.

"You could even have a go at firing it if you wanted to take it out tomorrow."