Tell Luna to sit in your lap.

You glance over at Luna. She seems really into the movie, moving her head along with the roller derby girls on screen. She looks really cute while she's concentrating like that, and her tight "tennis" t-shirt shows off her full breasts to advantage. You think about how she's got no panties on under her short little skirt, and feel yourself chubbing up.

The four pairs of girl's underwear you're wearing are getting uncomfortably tight on your swelling cock. You glance at Kath, who is busy whispering to Jennifer on her other side. You look over at Luna again. She's so spacy ... you think she might be up for anything.

"Luna," you whisper, "Are these girls' panties ar really constrictive. How about I take my cock out, and you sit on my lap through the rest of the movie?"