How Betelgeuse captured Subaru's body like in the ending of episode 23? How Betelgeuse captured Subaru's body?

Spoiler alert if you didn't watch episode 25:


  In the ending of episode 23, he captured Subaru's body which some would think was possible because Subaru has touched the book. But he didn't touch it in episode 25 and still Betelgeuse was able to capture him.


How? Why?
In episode 23 at 11:40.


   When Julius was having a conversation with Subaru, he said that Subaru might have an affinity for spirits. Since Petelgeuse was a spirit himself, he could possess the fingers' body which had been cast spell on beforehand and even entities having affinity for spirits. According to Julius, Subaru definitely matches the case.