It has been around five minutes since Rudy started eating Jane's cave.
"Mnh~" Jane moaned with Rudy's snake in her mouth.
When Rudy first mentioned he wanted Jane to feel good, Jane assumed he was going to finger her again, which was the only pleasure she was aware of.
She had no knowledge of oral sex or foreplay, only the sex. IT seemed the vampires liked to jump right on and do the deed, which was followed and mentioned in the ancient books that were used to give knowledge to the young vampires such as Rias and Jane when they were still young.
So when she realized Rudy was licking her cave, she tried to stop him by saying it was dirty and all the things an innocent maiden would say. But after Rudy showed his skills, Jane couldn't dare to stop him. Not because she was afraid of angering Rudy, but because she didn't want the pleasure to end.