The next shot depicts a cross behind him, created by the fan
Then, a fan reappears in episode 25, twice, during Misato's instrumentality as Shinji watches her having sex with Kaji.
The scene is repeated in EoE, but this time, Misato's feet are visible and Shinji's holding her cross.
Lastly, there's a real image of a fan in episode 26 that's shown while Misato tells Shinji that he doesn't have a logical reason to be insecure:
Edited lightly to remove unneeded spoilers around plot details and add spoiler tags to enormous images. -Reichu