I 19F was at the library watching porn and masturbating in the corner when a girl who I'll call Ashley caught me and came over. I quickly tried to hide it but she had seen everything. She seemed more surprised than anything but she just told me I can finish up while we chat. While I was finishing up she told me she lived in an apartment nearby and she was also gonna masturbate in this corner. She invited me back to her place to get a little dirty and I'll almost always agree to a nice sesh. At first I thought it was pretty cool that she lived in my apartment building but then I found out she's my downstairs neighbor. When I told her this she kinda chuckled and told me she gets off to my loud moaning in the middle of the night. When we started on the couch it was mostly a lot of teasing and stuff. We didn't really do any fucking but mostly a lot of eating and teasing with vibes.